Molbank doi: 10.3390/M2170

Authors: Pascal Pigeon

The ferrocidiphenol family brings together anticancer molecules featuring a [ferrocene-alkene-(p-phenol)2] motif that can form upon oxidation a quinone methide metabolite targeting cellular proteins. Adding an imide group (imido-ferrocidiphenol) dramatically enhanced the anticancer activity of ferrocidiphenol. We aimed to explore whether molecules with two ferrociphenol motifs connected by bisimide moieties could provide even more effective compounds. Using amino-ferrocidiphenol and commercial bisanhydrides at reflux, for the first time, three symmetrical and bent bis(imido-ferrocidiphenols) were synthesized, with moderate yields, and characterized. However, these compounds were insoluble in most common organic solvents and unstable. This likely explains why their anticancer activity was nil.

Molbank doi: 10.3390/M2169

Authors: José María Peña-Martínez Jesús Alberto Rojas Morales Luis Ramiro Caso-Vargas Elizabeth Bautista-Rodríguez Joel L. Terán Alan Carrasco-Carballo

The synthesis of three novel, valuable bioconjugates obtained by coupling cholesterol bromoacetate with pyridine derivatives via an SN2 reaction was successfully carried out. Each of the products was fully characterized by magnetic nuclear resonance (1H, 13C, APT, 1H−1H COSY, 1H–13C HMBC, 1H–13C HSQC), infrared spectroscopy (IR), and high-resolution mass spectrometry (HRMS).

Molbank doi: 10.3390/M2168

Authors: Rumen Lyapchev Maria Ivanova Iskra Z. Koleva Dimitar Shandurkov

A new compound, 2-(2-methoxyphenyl)-4-methyl-6-nitroquinoline, was obtained via Suzuki reaction. An unexpected side product, 2-(2-methoxyphenyl)-4-methylquinolin-6-amine, was isolated. The structures of the novel compounds were confirmed by 1H, 13C and 2D-NMR. Their optical properties were also studied.

Molbank doi: 10.3390/M2167

Authors: Alan Aguilar-Aguilar Ángel Palillero-Cisneros Félix May-Moreno Jorge R. Juarez-Posadas Joel L. Terán David M. Aparicio

Herein, starting from (R)-(+)-α-methylbenzylamine, we report an efficient synthesis and full characterization of a new (R)-3-(1-hydroxyethylidene)-1-(1-phenylethyl)piperidine-2,4-dione, a new tetramic acid analog. The key steps involved a non-classical Corey–Chaykovsky intramolecular cyclization reaction to access the corresponding zwitterion, followed by a sequential desulfurization/reduction and condensation procedure. The titled product was obtained in five steps, and the desired product 7 with an overall 58% yield.

Molbank doi: 10.3390/M2166

Authors: Matevž Schweiger Luka Ciber Nejc Petek Franc Požgan Jurij Svete Bogdan Štefane Uroš Grošelj

LiAlH4 reduction of tert-butyl (S)-butyl(1-((2-cycloheptylethyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (1) gave imidazolidine 2, while treatment with lithium diisopropylamide furnished the β-elimination product, cinnamamide 3. Both products were fully characterized. Reductive cyclization of N-alkylated-N-Boc-protected amino acid amides with LiAlH4 may be a viable synthetic method for trisubstituted chiral imidazolidines.

Molbank doi: 10.3390/M2165

Authors: Julia I. Pavlenko Mikhail S. Novikov Anastasiya V. Agafonova

2-Aminonicotinonitriles represent an important class of heterocycles with diverse biological activities. Herein, we report an unexpected photochemical transformation of azirine-2-carboxylic acids leading to the formation of 2-aminonicotinonitrile derivatives. Optimization of the reaction conditions enabled the synthesis of the target products in moderate yields. The structure of the obtained product was confirmed by NMR spectroscopy, HRMS, and single-crystal X-ray diffraction analysis.

Molbank doi: 10.3390/M2164

Authors: Yuki Itabashi Kei Ohkubo

9-Mesitylacridinium salts are widely recognized as efficient organic photoredox catalysts owing to their strong excited-state oxidizing power and stability under visible-light irradiation. In this study, a new mesityl acridinium derivative bearing a di-tert-butylphenyl substituent on the nitrogen atom was synthesized. The introduction of tert-butyl groups on the N-aryl moiety was primarily aimed at improving solubility and chemical stability of the acridinium salt. Starting from a 9(10H)-acridinone precursor, the target compound was obtained in high overall yield through a concise synthetic sequence. The synthesis consists of a copper-catalyzed C–N coupling reaction to install the aryl substituent on the nitrogen atom, followed by a Grignard reaction and subsequent acid treatment to afford the corresponding acridinium salt. All transformations proceeded smoothly, providing efficient access to the desired novel acridinium derivative. This work presents a practical example of the structural modification of mesitylacridinium derivatives directed toward enhanced solubility and stability, and provides a useful synthetic platform for the preparation of structurally diverse acridinium salts.

Molbank doi: 10.3390/M2163

Authors: Yordan Stremski Maria Bachvarova Stela Statkova-Abeghe Plamen Angelov

2-methylcamalexin, a novel derivative of the phytoalexin Camalexin, was synthesized for the first time, using a convenient two-step approach. The approach realizes coupling of two aromatic heterocyclic moieties (2-methylindole and thiazole) by sequential α-amidoalkylation/oxidative re-aromatization. The target product was obtained in a cost-effective manner, with 88% yield over two steps. The structure of the synthesized product was unequivocally determined on the basis of NMR, HRMS and FTIR spectral measurments.

Molbank doi: 10.3390/M2162

Authors: Richard M. Beteck Lesetja J. Legoabe

Herein we reported on a one-pot nitro reduction/nucleophilic aromatic substitution on 1-(2-fluoro-5-nitrophenyl)ethan-1-one using a mixture of acetic acid and iron powder in ethanol. The resultant target compound, a nitrated N bis-acetophenone, has many reactive handles; as such, it is a novel intermediate that can be deployed for the syntheses of a vast array of compounds not reported before. This compound is fully characterized using 1H and 13C NMR spectroscopy, and HRMS.

Molbank doi: 10.3390/M2161

Authors: Maria Annunziata M. Capozzi Cosimo Cardellicchio

As a part of our research on the presence of conglomerates among the aryl benzyl sulfoxides, racemic-benzimidazolyl pentafluorobenzyl sulfoxide was synthesised, and its crystal structure was determined by a single crystal X-ray diffraction experiment. The main interactions building up the crystal structure were recognised and compared with those of similar compounds. Since the crystal structures of racemic and enantiopure benzimidazolyl pentafluorobenzyl sulfoxides are different, the presence of a conglomerate is excluded in the present case.

Molbank doi: 10.3390/M2160

Authors: Eder Y. Nolasco-Terrón David Gómez-Colín Nelly González-Rivas Diego Martínez-Otero Erick Cuevas-Yañez

1-Phenyl-4-p-tolyl-[1,2,3]triazole was obtained via a CuAAC reaction involving phenyl azide and 1-ethynyl-4-methylbenzene. The NMR spectra of the compound are discussed, and its crystal structure was studied by X-ray analysis. According to the latter analysis and a Hirshfeld surface analysis, the predominant intermolecular C-H⋅⋅⋅N and C-H⋅⋅⋅π interactions in this molecule are responsible for crystal packing.

Molbank doi: 10.3390/M2159

Authors: Roderick Abdilla Stefano Volpi Alessandro Casnati Maria A. Cardona Ruben Gatt

This paper describes the synthesis and characterisation of the calix semitube 5. The calix[4]semitube consists of two calix[4]arenes connected through their lower rim from two phenol groups in distal positions. One calix[4]arene is unsubstituted on its upper rim, while the upper rim of the other calix[4]arene has two nitro groups in the 1,3- position and two tert-butyl groups in the remaining ones. The synthesis procedure yielded an amorphous structure, which did not provide a single crystal. The final compound was comprehensively characterised by infrared spectroscopy, mass spectrometry, and 1H and 13C NMR spectroscopy. The results of the 1H NMR spectroscopy confirmed that the calix[4]arene units adopted a cone conformation. This was confirmed by COSY and 1H-13C HMBC. The results obtained confirm that the compound was successfully synthesised. The IUPAC name of 5 is 2,34-di-tert-butyl-39,49-dinitro-6,7,8,9,27,28,29,30-octahydro-15H,21H,36H,42H-4,32:11,25-bis(methano [1,3]benzenomethano)-16,20:37,41-di(metheno)tetrabenzo[g,g1,p,x][1,6,18,23] tetraoxacyclotetratriacontine-43,46,54,60-tetraol.

Molbank doi: 10.3390/M2158

Authors: Desita Triana Aziz Resky Nugraha Marwah Wirda Ningsih Zetryana Puteri Tachrim Yuta Murai Makoto Hashimoto

A novel derivative from carotene-type sesquiterpene, (1S,2R,3aR,6S,8aS)-1-isopropyl-3a,6-dimethyldecahydroazulene-1,2,6-triol (1), was successfully isolated from filamentous fungus Trichoderma virens NBRC 31959. The structure and molecular formula of 1 were determined by interpretation of 1D and 2D NMR and HRMS data. The absolute configuration was established unambiguously by single-crystal X-ray diffraction, with the Flack parameter supporting the assignment. This study adds to the chemical diversity of sesquiterpene-type CAF603 derivatives of Trichoderma virens.

Molbank doi: 10.3390/M2157

Authors: Hye Jin Kim Kye Jung Shin Khin Myo Htwe Kee Dong Yoon

Phytochemical investigation of Millettia racemosa Benth. led to the identification of an undescribed isoflavan, (+)-(3S)-8-(3-methylbut-2-en-1-yl)-7-methoxy-6,2′,4′-trihydroxyisoflavan, namely milletiaisoflavan (1). The structure of the isolate was elucidated by spectroscopic evidence (one- and two-dimensional nuclear magnetic resonance, ultraviolet, mass spectrometry, and circular dichroism spectra).

Molbank doi: 10.3390/M2156

Authors: Sara Ghazi Mohamed Touaibia

Phenolic acids are widely known for their antioxidant and biological properties, which make them attractive scaffolds for structural modification. In this short note, we report the synthesis of a new 3,4-di-glucosylated caffeic acid analogue. The (E)-3-(3,4-di-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyloxy)phenyl) acrylic acid was obtained through a two-step synthesis, starting with a phase-transfer-catalyzed glycosylation of 3,4-dihydroxybenzaldehyde with 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide followed by a Dobner-modified Knoevenagel condensation. Consistent with the 2-O-acetyl neighbouring participation and the resulting Walden-type inversion at the anomeric centre, both glucopyranosyl units were assigned the β-configuration.

Molbank doi: 10.3390/M2155

Authors: Yahaira Cuenú Ibargüen Fernando Cuenú-Cabezas Jovanny A. Gómez Castaño

This work reports the isolation and structural characterization of 1-(2-aminophenyl)-3-(4-pyridyl)-3-hydroxy-1-propanone (1), a β-hydroxyketone intermediate that crystallized unexpectedly during the base-catalyzed aldol condensation of 2-aminoacetophenone with pyridine-4-carbaldehyde, a reaction intended to afford the corresponding pyridyl chalcone (2). The formation of (1) highlights the sensitivity of Claisen–Schmidt reactions to the electronic and steric features of the substrates and to the applied reaction conditions. Single-crystal X-ray diffraction unambiguously confirmed the molecular structure of (1), revealing a hydrogen-bonding network involving the amino, carbonyl, and β-hydroxyl functionalities. These interactions contribute to the solid-state stabilization of the β-hydroxyketone and hinder its dehydration to chalcone (2). The present results provide experimental insight into the mechanistic landscape of aldol condensations and emphasize the relevance of isolable intermediates as structurally defined precursors for further synthetic transformations.

Molbank doi: 10.3390/M2154

Authors: Yongyao Li Hongtao Kong Xiaoying Huang Maxwell Ampomah-Wireko Cedric Dzidzor Kodjo Amengor En Zhang Yihong Zhao

Bicyclo[3.3.0]skeleton is a common structural motif present in many natural products and pharmaceutical agents. Here we have synthesized a rigid 3a-arylhexahydropentalene-1,6-dione from cyclopent-2-en-1-one which is an easy and readily available starting material.

Molbank doi: 10.3390/M2153

Authors: Jocelyn Pradegan Aurélien Crochet Katharina M. Fromm

The synthesis of a salen-type ligand functionalized with naphthalene moieties, as well as its precursor, are reported. The compounds were characterized by 1H and 13C NMR, ESI-MS spectrometry and single crystal X-ray diffraction.

Molbank doi: 10.3390/M2152

Authors: Diyana Dimitrova Nikol Dimova Dimitrina Velikova Iliyan Ivanov Dimitar Bojilov Stanimir Manolov

In this Short Note type article, we report the synthesis of a new hybrid molecule, N-(3,4-dimethoxyphenethyl)-2-propylpentanamide, using a solvent-minimized mechanochemical method that provides a simple and efficient synthetic approach. The process achieved high yield. The compound was confirmed by melting-point analysis, 1H and 13C NMR, IR spectroscopy, and mass spectrometry.

Molbank doi: 10.3390/M2151

Authors: Domenica Marabello Paola Benzi

Interest in non-centrosymmetric crystalline materials exhibiting second harmonic generation (SHG) has increased due to their potential applications in optical sensing and biosensing. Saccharide-based metal complexes are particularly attractive systems, as chiral sugars can promote non-centrosymmetric crystal packing. In this work, a new lanthanum–β-d-fructose compound, [La(C6H12O6)(H2O)5]Cl3 (LaFRUCl), was synthesized using a simple and low-cost method and characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group P212121 and consists of infinite (La3+–fructose)n chains extending along the [001] direction, forming a one-dimensional Metal–Organic Framework. The nonlinear optical response was evaluated using the Kurtz–Perry powder technique with a Nd:YAG laser (1064 nm) and compared to a sucrose reference. The measured SHG efficiency is comparable to that of previously reported alkaline earth metal–sugar analogs. While the compound’s SHG emission is significant, evaluation of its structural stability under aqueous or physiological conditions is be required before considering biological applications.

Molbank doi: 10.3390/M2150

Authors: Andreas S. Kalogirou Panayiotis A. Koutentis

Suzuki–Miyaura coupling of 3-chloro-5-[(2-ethylhexyl)amino]-4H-1,2,6-thiadiazin-4-one with phenylboronic acid, at ca. 100 °C, gave 3-[(2-ethylhexyl)amino]-5-phenyl-4H-1,2,6-thiadiazin-4-one in 69% yield. Another nucleophilic substitution reaction of 3-chloro-5-[(4-oxo-5-phenyl-4H-1,2,6-thiadiazin-3-yl)amino]-4H-1,2,6-thiadiazin-4-one with 2-ethylhexan-1-amine at ca. 100 °C gave 3-[(2-ethylhexyl)amino]-5-[(4-oxo-5-phenyl-4H-1,2,6-thiadiazin-3-yl)amino]-4H-1,2,6-thiadiazin-4-one in 93% yield.

Molbank doi: 10.3390/M2149

Authors: Andrej Bogataj Luka Ciber Nejc Petek Franc Požgan Jurij Svete Bogdan Štefane Uroš Grošelj

An alkene-tethered enaminone 7 was synthesized in four steps from bromoacetic acid and 3,3-dimethylallyl alcohol. The enaminone was fully characterized, including UV-Vis spectra. TBADT-catalyzed HAT of the alkene-tethered enaminone initiated a fragmentation that yielded the literature-known phenylacetone-derived enaminone.

Molbank doi: 10.3390/M2148

Authors: Michail N. Elinson Varvara M. Kalashnikova Yuliya E. Ryzhkova Oleg A. Rakitin

Spirocyclic compounds are experiencing a research surge due to their unique 3D structure, offering enhanced pharmacological, industrial, and material applications. They are increasingly used in medicinal chemistry to improve drug-like properties, such as solubility and target binding, and are also being utilized for advanced material applications, including electronics and photonics. In this communication, 3-(4-hydroxyphenyl)-1′,3′,6-trimethyl-2′H,3H,4H-spiro[furo[3,2-c]pyran-2,5′-pyrimidine]-2′,4,4′,6′(1′H,3′H)-tetraone was prepared via a two-stage transformation including a tandem Knoevenagel–Michael reaction and NBS-induced cyclization. At the first stage, a previously unknown ionic scaffold, morpholin-4-ium 5-((4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)(4-hydroxyphenyl)methyl)-1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate was also isolated. Structures of the newly synthesized compounds were established by 1H and 13C NMR, IR spectroscopy, high-resolution mass spectrometry, and elemental analysis.

Molbank doi: 10.3390/M2147

Authors: Lina A. Al-Dulaimi Joseph C. Bear Jeremy K. Cockcroft Giuseppe Trigiante Fawaz Aldabbagh

1,4-Dimethoxy-2,3-dinitrobenzene (1) reduction using sodium hydrosulfite resulted in 3,6-dimethoxybenzene-1,2-diamine (2) and 3,6-dimethoxy-2-nitroaniline (3) in 24% and 59% yields, respectively. Nitroaniline 3 was acetylated with acetyl chloride to give N-(3,6-dimethoxy-2-nitrophenyl)acetamide (4) in a 65% yield and with acetic anhydride to give N-acetyl-N-(3,6-dimethoxy-2-nitrophenyl)acetamide (5) in 78% yield. Novel compounds 4 and 5 were characterized by FT-IR, 1H and 13C-NMR, and HRMS. The X-ray crystal structure of acetamide 4 is also presented.

Molbank doi: 10.3390/M2146

Authors: Yong-Yao Li Zhi-Hao Li Xiao-Ying Huang Maxwell Ampomah-Wireko Cedric Dzidzor Kodjo Amengor En Zhang Yi-Hong Zhao

Owing to their distinctive physicochemical features, their structural analogues of benzene ring bioisosteres, and their strong affinity for biomacromolecules, pyridine derivatives function both as core structural scaffolds in pharmacologically active compounds and as versatile elements for optimizing key drug-like properties, such as water solubility, membrane permeability, and metabolic stability. In this study, we synthesized five pyridine-fused heterocyclic compounds using common synthetic intermediates as precursors.

Molbank doi: 10.3390/M2145

Authors: Cuicui Wang Jinhua Wang Yunkai Zhang Azura A. Rashid Siew Kooi Ong

This study investigates the rational design of a dinuclear zinc(II) coordination polymer, (C36H34Br2N8O4S2Zn2), to explore how halogen substitution and ligand choice modulate structural architecture, contributing to the development of functional coordination polymers with tailored properties. The complex was synthesized from a bromo-substituted semicarbazone Schiff base ligand (L1) and a rigid bipyridine linker (L2) under solvothermal conditions, and its structure was elucidated using single-crystal X-ray diffraction (SCXRD), complemented by characterization via powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and infrared (IR) spectroscopy. Crystallographic analysis reveals that the complex crystallizes in the triclinic space group P-1, forming discrete dinuclear units where each Zn(II) center adopts a distorted square–pyramidal geometry; these units are extended into one-dimensional chains by bridging L2 ligands and further assembled into a three-dimensional supramolecular network through hydrogen-bonding interactions. PXRD confirms the high phase purity of the bulk material, TGA indicates notable thermal stability up to 130 °C, and IR spectroscopy validates the coordination modes and hydrogen-bonding network. This work elucidates the critical role of the bromo substituent and rigid ancillary ligands in modulating the solid-state structure of the zinc(II) complex. The revealed structure-directing principles provide a valuable reference for the rational design of functional coordination polymers.

Molbank doi: 10.3390/M2144

Authors: Andrii Yu. Myshastyi Sergiy V. Vlasov Hanna I. Severina Georgiy G. Yakovenko Andrii R. Khairulin

An effective one-step synthetic procedure for preparation of hydroxylated analogues of ethyl 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate as novel promising multifunctional building blocks for drug discovery based on the Gewald procedure was developed.

Molbank doi: 10.3390/M2143

Authors: Nikita A. Tretyakov Andrey N. Maslivets

The reaction of 4,4-dimethyl-8-(4-methylbenzoyl)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-1,6,7-trione with thioacetamide in a 1:1 ratio when refluxed in dichloromethane gives (4S*,10aS*,11S*)-4-hydroxy-2,7,7-trimethyl-11-(4-methylbenzoyl)-7,8-dihydro-10H-4,10a-methano[1,4]oxazino[3,4-d][1,3,5]thiadiazepine-5,10(4H)-dione with a good yield. This compound was fully characterized.

Molbank doi: 10.3390/M2142

Authors: Dmitry V. Osipov Pavel E. Krasnikov Vitaly A. Osyanin

A DABCO-catalyzed one-pot synthesis of a novel pentacyclic heterocycle featuring an unprecedented benzo[4,5]imidazo[1,2-a]chromeno[3,2-e]pyridine scaffold from 2-(cyanomethyl)benzimidazole and 3-trifluoroacetyl-4-phenyl-4H-chromene has been developed. This hybrid architecture merges three privileged pharmacophores—benzimidazole, chromene, and pyridine—into a rigid, nearly planar π-extended system decorated with trifluoromethyl and nitrile groups. The structure of 8-phenyl-13a-(trifluoromethyl)-13aH-benzo[4,5]imidazo[1,2-a]chromeno[3,2-e]pyridine-6-carbonitrile was unambiguously confirmed through NMR spectroscopy and X-ray diffraction analysis. A plausible mechanism involves Michael addition, hemiaminal formation, ring opening, recyclization, and oxidation.

Molbank doi: 10.3390/M2141

Authors: Jorge Trilleras Efraín Polo-Cuadrado Jairo Quiroga

The synthesis of methyl (E)-3-(2-amino-4-chloro-6-morpholinopyrimidin-5-yl)acrylate 3 was accomplished using a Schlosser-modified Wittig reaction. Complete 1H and 13C NMR signal assignments confirm the formation of E-alkene.

Molbank doi: 10.3390/M2140

Authors: Yuhan Xie Alessandra Gianoncelli Imran Khan Giovanni Ribaudo Paolo Coghi

In this report, we describe the synthesis and full spectroscopic characterization of a previously unreported podophyllotoxin (PTOX) analogue bearing a second 3,4,5-trimethoxyphenyl (TMP) unit at the C-4 position through an ester linkage. This dual-TMP PTOX derivative is obtained from a brominated PTOX intermediate. In this precursor, the bromine atom is located on the TMP aromatic ring at the 2′-position. The new compound was fully characterized by proton (1H), carbon-13 (13C), heteronuclear single-quantum coherence (HSQC), and distortionless enhancement by polarization transfer (DEPT) NMR spectroscopy. Ultraviolet–visible (UV-Vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, mass spectrometry and elemental analysis were also performed to confirm the structure and purity of the synthesized ester derivative.

Molbank doi: 10.3390/M2139

Authors: Laurence J. Taylor Philip Pickett David B. Cordes Petr Kilian

Peri-substituted bis(tertiary) phosphine-arsine Acenap(PiPr2)(As(SPh)Ph) (4, Acenap = acenaphthene-5,6-diyl) was synthesized by the reaction of the chloroarsine (PiPr2)(AsPhCl) with PhSLi. The X-ray crystal structure of this compound reveals an intramolecular P∙∙∙As–Cl pnictogen bond, with the phosphorus lone pair donating into the As–S σ* orbital.

Molbank doi: 10.3390/M2138

Authors: Thomas Gelbrich Johanna Freilinger Gabriel Partl Herwig Schottenberger Volker Kahlenberg Jan Back Sven Nerdinger

Vinylimidazolium salts constitute a highly relevant class of polymerizable heterocycles, especially in the field of so-called polymer ionic liquids (PILs), and they are frequently used as components of polyelectrolytes. Therefore, crystallographic characterizations, in particular studies of charge distribution and conformational features, can provide fundamental insights concerning ion–ion and ion–dipole interactions. The structure of the title compound [1046127-79-0] has the space group symmetry P21/c. Its asymmetric unit contains one formula unit, consisting of two bromide anions and the halves of two cation moieties. The cation units possess inversion symmetry, and their C6H12 chains adopt an all-trans conformation.

Molbank doi: 10.3390/M2137

Authors: Vincenzo Piccialli Nicola Borbone Monica Terracciano

As a part of an SAR study aimed at testing the antitumor activity of some C15 acetogenins related to mycalin A, we report here the synthesis of the C-1 debromo-derivative of laurenciallene, a substance recently isolated from the red alga Laurencia obtusa. This new substance has been obtained by the selective, reductive debromination of the terminal bromoallene moiety of laurenciallene with Zn/AcOH. Its structure has been fully characterized by spectral methods, including 2D-NMR spectra.

Molbank doi: 10.3390/M2136

Authors: Qing-Qing Wan Zhi-Cheng Fu

Here, we synthesized 2,3,4,6-tetra(9H-carbazol-9-yl)benzonitrile (4CzHPN) via visible-light-driven photocatalytic monodecyanation using the versatile metal-free catalyst 4CzIPN. Characterized by NMR, IR, X-ray diffraction, and DFT calculations, it features a 3.49 eV HOMO-LUMO gap and shows blue-shifted absorption/emission, emerging as a promising advanced metal-free photoredox catalyst.

Molbank doi: 10.3390/M2135

Authors: Mihaela Cristea Sergiu Shova Marcel Mirel Popa Florea Dumitrascu

The title compound 2-iodopyridin-3-yl acetate was obtained by acetylation of the OH group of 2-iodo-3-hydroxypyridine. Knowing that the hydroxyl group, as a strong H-bond donor in halogenated hydroxypyridines, usually directs supramolecular packing and might enforce possible halogen–halogen contacts, we crystallized 2-iodo-3-acetoxypyridine with the aim of disrupting the most important H-bond donor and assessing the propensity of the iodine for halogen bond formation. Indeed, in the compound 2-iodopyridin-3-yl acetate, the crystal packing is characterized by infinite 3D chains bonded through I···O=C and C-H···I contacts between adjacent molecules. These chains are interconnected by weak C-H···O contacts, implying the presence of oxygen in the ester. The I···H contact with the C-H axis perpendicular to the electron belt of the iodine atom can enhance the σ-hole of the iodine and act cooperatively in crystal cohesion. No halogen–halogen contacts were present.

Molbank doi: 10.3390/M2134

Authors: Ilia A. Pilipenko Olga Yu. Ozerova Oleg P. Demidov Ruslan I. Baichurin Oussama A. Mammeri Sergey V. Makarenko

The previously unknown compounds—3-(dichloromethyl)-2-nitro-6,7-dihydro-1-benzofuran-4(5H)-ones—have been synthesized and structurally characterized via single-crystal X-ray diffraction, 1H, 13C–{1H}, 1H–13C HMQC and 1H–13C HMBC NMR spectroscopy, IR, and UV spectroscopy.

Molbank doi: 10.3390/M2133

Authors: Mara Plotniece Krista Arule Karlis Pajuste Aiva Plotniece Arkadij Sobolev

Indane-1,3-dione and 1,4-dihydropyridine (1,4-DHP) scaffolds are of significant interest in medicinal chemistry. Herein, we report the synthesis characterization of a new lipid-like indane-1,3-dione–1,4-DHP betaine, 2-(3′,5′-bis((dodecyloxy)carbonyl)-2′,6′-dimethyl-1′,4′-dihydro-[3,4′-bipyridin]-1-ium-1-yl)-1,3-dioxo-2,3-dihydro-1H-inden-2-ide (3). Compound 3 was synthesized from 2,2-dicyanomethylideneindan-1,3-dione (1) oxide and a didodecyl-substituted 1,4-DHP derivative 2 and characterized by UV–Vis spectroscopy, 1H-NMR, 13C-NMR, and HRMS. The obtained results demonstrate a promising strategy for the design of delivery agents, exploiting the lipid-like properties of the synthesized betaine.

Molbank doi: 10.3390/M2132

Authors: Diyana Dimitrova Tsvetelina Marinova Reni Bozhanova Iliyan Ivanov Dimitar Bojilov Gabriel Marc Stanimir Manolov

Herein, we report the mechanochemical synthesis of a novel hybrid molecule, N-(4-methoxyphenethyl)-2-propylpentanamide. This solvent-minimized synthesis aligns with the principles of Green Chemistry and exemplifies the emerging paradigm of medicinal mechanochemistry, offering an efficient, sustainable route to pharmaceutically relevant amides. The newly synthesized compound was fully characterized by melting point determination, 1H and 13C NMR spectroscopy, infrared (IR) spectroscopy, and mass spectrometry.

Molbank doi: 10.3390/M2131

Authors: Silvia Rizzato Massimo Moret

We report the crystallization and single-crystal X-ray analysis of the monohydrate hydrochloride salt of chloroquine(CQ), abbreviated CQHCl·H2O, an antimalarial drug with the formula C18H26ClN3. The crystal structure reveals a well-defined supramolecular architecture stabilized by an extensive hydrogen-bonding network involving CQH+ cations, chloride anions, and water molecules. Notably, this study provides the first crystallographic characterization of a monoprotonated chloroquine salt. Additionally, our findings demonstrate the feasibility of isolating pseudo-polymorphic forms of a commercially available CQ salt via heterogeneous crystallization.

Molbank doi: 10.3390/M2130

Authors: Denis A. Tiunov Victor A. Tafeenko Alexander V. Kurkin

(2RS,3aRS,9aRS)-3a-methyl-2-phenyl-3,3a,9,9a-tetrahydro-1H-benzo[f]indol-4(2H)-one hydrobromide was first synthesized via a tandem aza-Cope rearrangement and Mannich reaction from (1RS,2SR)-2-amino-1-(prop-1-en-2-yl)-2,3-dihydro-1H-inden-1-ol, which, in turn, was obtained in four steps from commercially available 2,3-dihydro-1H-inden-1-one. The molecular and crystal structure features of the new compounds were characterized using NMR spectroscopy (1H, 13C spectra).

Molbank doi: 10.3390/M2129

Authors: Abderrahim Khatyr Isabelle Jourdain Michael Knorr Carsten Strohmann Tobias Schrimpf

The addition of 3-isocyanatopropyltriethoxysilane and 2-aminonaphthalene in THF affords the title compound 1-(naphthalen-2-yl)-3-(3-(triethoxysilyl)propyl)urea 1. A determination of the crystal structure of this naphthyl urea reveals the occurrence of strong intermolecular N-H···O hydrogen bonds, giving rise to a 1D supramolecular ribbon, whose interactions have also been assessed by a Hirshfeld surface analysis. The propensity of 1 to sense halide ions by intramolecular trapping through N-H···Hal bonding was also investigated by UV-vis spectroscopy and fluorescence measurements.

Molbank doi: 10.3390/M2128

Authors: Young Hee Lee Jae-Kyung Jung

2-({3-[2-(1-cyclohexen-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}sulfanyl)-N-(4-ethylphenyl)butanamide (K284-6111; K284), the representative CHI3L1 inhibitor, has interesting biological activities, including anti-cancer and anti-inflammatory effects on neuroinflammation. Following our hit-to-lead program, we report the most active novel derivative, named CBJL-025, 2-((6,7-dimethoxy-4-oxo-3-(4-(trifluoromethyl)phenethyl)-3,4-dihydroquinazolin-2-yl)thio)-N-(4-ethylphenyl)butanamide. The title compound, CBJL-025, was successfully synthesized by S-alkylation of the p-trifluoromethyl phenethyl group possessing quinazoline and the corresponding bromide. The structure of CBJL-025 was confirmed by 1H and 13C nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS).

Molbank doi: 10.3390/M2127

Authors: Adriana Grozav Cristina Azarov Gabriel Marc Adrian Pîrnău Stanimir Manolov Ovidiu Oniga Ovidiu Crișan

This study presents the synthesis of a new compound, ethyl 2-(2-((6-methyl-4-oxo-4H-chromen-3-yl)methylene)hydrazinyl)thiazole-4-carboxylate, obtained by the Hantzsch heterocyclisation reaction. The compound was analyzed through melting point determination, 1H and 13C NMR spectroscopy, infrared, and UV spectroscopy.

Molbank doi: 10.3390/M2126

Authors: Navaratnarajah Kuganathan Tharmarajah Manoranjan

A phytochemical investigation of Myristica ceylanica resulted in the identification of seven arylalkanone-derived phenolic compounds, comprising one new naturally occurring arylalkanone (A), two derivatives (A1 and A2) prepared by chemical synthesis, and four known malabaricones (B–E). Density functional theory (DFT) calculations were conducted to evaluate the geometries, electronic properties, and charge distributions of the newly identified arylalkanone and its derivatives and to compare them with those of malabaricones B–E. The arylalkanones exhibited geometrical features comparable to those of the malabaricones, whereas frontier molecular orbital analysis revealed similar HOMO–LUMO energy gaps for the malabaricones but a progressive widening of the gap among the arylalkanone derivatives, indicating enhanced electronic stabilisation. Mulliken population analysis identified oxygen atoms as the principal electron-rich sites in both series, with arylalkanones displaying greater charge polarisation and increased sensitivity to structural substitution.

Molbank doi: 10.3390/M2125

Authors: Andreas S. Kalogirou Panayiotis A. Koutentis

Reactions of 3′,5′-dichlorospiro(benzo[d][1,3]dioxole-2,4′-[1,2,6]thiadiazine) or 6,10-dichloro-1,4-dioxa-8-thia-7,9-diazaspiro[4.5]deca-6,9-diene with ammonia in MeCN, at ca. 20 °C, gave 5′-chlorospiro(benzo[d][1,3]dioxole-2,4′-[1,2,6]thiadiazin)-3′-amine and 10-chloro-1,4-dioxa-8-thia-7,9-diazaspiro[4.5]deca-6,9-dien-6-amine, respectively, in near quantitative yields.

Molbank doi: 10.3390/M2124

Authors: Hannah K. Lawley Bailey N. Baxter Caleb N. Lopansri Mary Helene Marmande Kathryn N. Mayeaux Lucy A. Orr David C. Forbes

Overexpression of protein phosphatase 5 (PP5) is implicated in tumor cell growth, establishing PP5 as a compelling target for small-molecule anticancer therapy. Building on prior success in achieving selectivity within the PP2A domain through scaffold functionalization that maximizes active-site interactions, we propose a parallel strategy for PP5 inhibition. Norcantharidin, the demethylated cousin of cantharidin, is a potent yet unselective phosphatase inhibitor, making its bicyclic framework an attractive platform for systematic derivatization. The approach reported herein exploits anhydride reactivity to generate a carboxylic acid derivative that is transformed into a chloromethyl ester. Chloromethyl ester functionality serves as a strategically activated intermediate enabling downstream functional-group diversification under mild, neutral conditions while preserving scaffold integrity. This modular synthetic strategy establishes a foundation for the development of PP5-selective norcantharidin derivatives with improved tumor selectivity, potency, and synthetic feasibility.

Molbank doi: 10.3390/M2123

Authors: Diyana Dimitrova Iliyan Ivanov Simona Ilieva Ivelina Cherneva Dimitar Bojilov Stanimir Manolov

Herein we describe the synthesis of N-(2-(1H-indol-3-yl)ethyl)-2-propylpentanamide. The compound was comprehensively characterized using melting-point analysis, 1H and 13C NMR spectroscopy, infrared spectroscopy, and mass spectrometry. The collective analytical results confirm the successful synthesis and structural integrity of the target molecule.

Molbank doi: 10.3390/M2122

Authors: Roman A. Irgashev Alexander S. Steparuk Gennady L. Rusinov Ildar R. Sayarov Alexey E. Aleksandrov Alexey R. Tameev

A symmetrical rubrene derivative, 5,6-bis(4-(methoxycarbonyl)phenyl)-11,12-diphenyltetracene, was synthesized via the thermal dimerization of 1,1-diphenyl-3-[4-(methoxycarbonyl)phenyl]-3-chloroallene. The reaction proceeded with the low selectivity typical of the classical “rubrenic synthesis” under these conditions, affording the target tetracene and the bis(alkylidene)cyclobutene by-product in nearly equal yields of 25% each. The optical characteristics of this rubrene derivative were investigated, revealing bright orange fluorescence in a CHCl3 solution (λem = 565 nm, ΦF = 0.81, τ = 11.41 ns), which is strongly quenched in the solid state (ΦF = 0.01) due to aggregation.

Molbank doi: 10.3390/M2121

Authors: Elizaveta I. Samorodova Anastasia R. Kovrizhina Andrei I. Khlebnikov

A novel unsymmetrical azine, 6-((2-oxoindolin-3-ylidene)hydrazineylidene)indolo[2,1-b]quinazolin-12(6H)-one, was synthesized through a condensation reaction between tryptanthrin-6-hydrazone and isatin in chloroform under reflux conditions. Structural characterization revealed the compound exists as a mixture of geometric isomers with one predominant form. Density functional theory (DFT) calculations identified the E,E configuration as the most stable isomer. The isomerization barriers for both C=N bonds were calculated at approximately 18.5 kcal/mol via nitrogen inversion. Given the established biological activities of tryptanthrin and isatin derivatives, this hybrid azine represents a promising lead compound for developing bifunctional drug candidates.

Molbank doi: 10.3390/M2120

Authors: Haoni Wang Meiting Zhang Jianwei Wu Junqi Zhang Xianglong Meng Yuliang Yang

A cyclometalated platinum(II) complex [Pt(bzq)(BINAP)]PF6 bearing a 2,2′-bis(diphenylphosphino)-1,1′-binaphthalene (BINAP) auxiliary ligand and a cyclometalated benzo[h]quinoline (bzq) ligand have been prepared. Structural characterization was achieved through X-ray crystallography, 1H, 13C and 31P NMR spectroscopy, ESI−MS, and elemental analysis.

Molbank doi: 10.3390/M2119

Authors: Diana Becerra Diana Hurtado-Rodríguez Juan-Carlos Castillo

We report an efficient and transition-metal-free protocol for the propargylation of 4-(4-chlorophenyl)-2-oxo-6-phenyl-1,2-dihydropyridine-3-carbonitrile using propargyl bromide in the presence of cesium carbonate in dimethylsulfoxide under mild conditions. This synthetic transformation proceeds with marked chemoselectivity, furnishing the O-propargylated pyridine and the N-propargylated 2-pyridone in 75% and 8% yields, respectively. Both products were fully characterized by IR and NMR spectroscopy, as well as high-resolution mass spectrometry, confirming their molecular structures.

Molbank doi: 10.3390/M2118

Authors: Anna A. Moroz Maksim V. Dmitriev Andrey N. Maslivets

The 1,4-dipolar cycloaddition of the ylidene derivative of 1H-pyrrole-2,3-dione to a dipole generated in situ from 1-benzylbenzimidazole and dimethyl acetylenedicarboxylate proceeds via the exocyclic multiple bond of the ylidene derivative and affords a mixture of diastereomeric spiro[benzo[4,5]imidazo[1,2-a]pyridine-3,3’-pyrroles], which slowly epimerized in a solution.

Molbank doi: 10.3390/M2117

Authors: Werner Seebacher Antoine Dupé Eva-Maria Pferschy-Wenzig Robert Saf Theresa Hermann Robert Weis

The reaction of aliphatic aldehydes with the tautomers 6,6-dimethyl-4-hydroxy-2H-thiopyrane-2-thione and 6,6-dimethyl-2-mercapto-4H-thiopyrane-4-one is reported to yield spiro compounds. However, the spiro compound of the reaction with formaldehyde is postulated, but has not been isolated to date. Due to a change in reaction conditions, we managed to isolate (RS)-6,6,7′,7′-Tetramethyl-2-sulfanylidene-5,6,6′,7′-tetrahydro-2H,2′H,4H,4′H,5′H-spiro[thiopyran-3,3′-thiopyrano [2,3-b]thiopyran]-4,5′-dione for the first time. The structure was proven with the help of a single X-ray crystal analysis. Furthermore, the new compound was fully characterized using one- and two- dimensional NMR techniques such as 1H, 13C, DEPT, COSY, HSQC and HMBC spectra, as well as IR and HRMS measurements.

Molbank doi: 10.3390/M2116

Authors: Dzhamilia N. Belozerova Maksim V. Dmitriev Irina V. Mashevskaya

A novel spiro-pyrrolothiazole derivative bearing a 2-oxindole substituent was synthesized and characterized. The compound was prepared via a catalyst-free reaction under mild conditions and isolated using a straightforward workup procedure. The structure of the synthesized title compound was confirmed with 1H, 13C NMR spectra and X-Ray diffraction data.

Molbank doi: 10.3390/M2115

Authors: Ivan Alekseev Dmitry Cheshkov Alexander Gorbunov Vladimir Kovalev Ivan Vatsouro

A cone calix[4]arene having one tert-butyl group and three amino groups at the wide rim was bis-N-protected stepwise using sulfonylation with 4-nitrobenzylsulfonyl chloride, followed by acylation with di-tert-butyl dicarbonate. The selective sulfonylation was shown to prefer the amino group located in the proximal calixarene aromatic unit relative to the tert-butylated moiety, resulting in the formation of an inherently chiral calix[4]arene with a wide-rim substitution pattern of AABC type. Further acylation of one of the two remaining amino groups also proceeded selectively. It involved the calixarene aromatic unit adjacent to the sulfonylated moiety, as clearly demonstrated by 2D NMR data for the ABCD-substituted reaction product, which was obtained as a mixture of enantiomers. The mixture was acylated with (R)-mandelic acid succinimide ester, and the resulting diastereomers were separated by conventional column chromatography, thus demonstrating the applicability of the stepwise protection strategy for the further preparation of enantiopure calix[4]arene cores possessing inherent chirality due to four different substituents at their wide rims.

Molbank doi: 10.3390/M2114

Authors: Diyana Dimitrova Yoana Barakova Ivaylo Trifonov Iliyan Ivanov Dimitar Bojilov Stanimir Manolov

Herein, we present the synthesis of N-(3-methoxyphenethyl)-2-propylpentanamide, a derivative of valproic acid. The compound has been thoroughly characterized through melting-point determination, 1H and 13C NMR spectroscopy, infrared spectroscopy, and mass spectrometry. The comprehensive analytical data obtained from these techniques confirm the successful preparation and structural integrity of the newly synthesized molecule.

Molbank doi: 10.3390/M2113

Authors: Maria Annunziata M. Capozzi Joan F. Piniella Febrer Cosimo Cardellicchio

Benzyl 2,4-dichlorophenyl sulfoxide was synthesized both in racemic and in an enantiopure form. This enantiopure sulfoxide is a further successful confirmation of our straightforward protocol to yield easily chiral aryl benzyl sulfoxides. We solved also the crystal structure of racemic benzyl 2,4-dichlorophenyl sulfoxide with a single crystal X-ray diffraction experiment. The main interactions building up the crystal structure were recognized and compared with other similar sulfoxides.

Molbank doi: 10.3390/M2112

Authors: Václav Hron Martin Urban Tomáš Tobrman

In 2019, carbamates derived from 3-hydroxypyridine were classified as nerve agents and subsequently included in the Annex on Chemicals by the Conference of the States Parties. Herein, we describe the preparation of a structural simulant of this class of compounds, 10-hydroxy-N,N-dimethyl-N-((3-(tosyloxy)pyridin-2-yl)methyl)decan-1-aminium bromide. The compound was synthesized via tosylation of 2-((N,N-dimethylamino)methyl)pyridin-3-ol with tosyl chloride in the presence of sodium hydride, followed by alkylation of the resulting ((N,N-dimethylamino)methyl)pyridin-3-yl 4-methylbenzenesulfonate with 10-bromodecan-1-ol.

Molbank doi: 10.3390/M2111

Authors: Elżbieta Speina Krzysztof Łyczko Adam Mieczkowski

Perimidine derivatives are versatile heterocycles with growing significance in medicinal chemistry and materials sciences. However, their structural variety remains limited. This study focused on the synthesis and crystal structure characterization of a new perimidine-based molecule. A bicyclic perimidine lactone, (1S,4R)-4,7,7-trimethyl-1-(1H-perimidin-2-yl)-2-oxabicyclo[2.2.1]heptan-3-one (1), was synthesized through an intramolecular dehydration of a monoamide intermediate formed from 1,8-diaminonaphthalene and (1S)-(–)-camphanic chloride under basic conditions. The product was purified and crystallized from acetone, giving single crystals suitable for X-ray diffraction. Structural analysis revealed two stereogenic centers and crystallization in the chiral tetragonal P43212 space group, with stabilization through N—H···O and C—H···N hydrogen bonds as well as C—H···π interactions.

Molbank doi: 10.3390/M2110

Authors: Kaichen Guan Jinzheng Yu Yangzhonghui Chen Jianqin Chen Qian Zhao Xiaojiang Hao Juan Xu Xiao Ding

Friedelin, a pentacyclic triterpene, has been reported to inhibit potential reactive oxygen species (ROS)-scavenging activity. Accordingly, we modified the structure of this compound with the aim of obtaining derivatives. A new derivative (compound 4), with an α,β-unsaturated ketone moiety, was synthesized via an aldol condensation. Structural characterization of this compound was performed using nuclear magnetic resonance (NMR) spectroscopy and high-resolution electrospray ionization mass spectrometry.

Molbank doi: 10.3390/M2109

Authors: Roman A. Irgashev Nikita A. Kazin

We report the first synthesis of 3,5-diamino-substituted dithieno[3,2-b:2′,3′-d]thiophene derivatives, bearing alkoxycarbonyl or acetyl groups at C-2 and C-6 positions. The target compounds were prepared via the reaction of 3,4-dibromothiophene-2,5-dicarbonitrile with alkyl thioglycolates or mercaptoacetone in the presence of DBU and isolated in 67–87% yield. The key dinitrile was synthesized in 76% yield from 3,4-dibromothiophene-2,5-dicarbaldehyde. In turn, this dialdehyde was prepared on a multigram scale from commercially available 2,5-dimethylthiophene in three steps. The resulting dithieno[3,2-b:2′,3′-d]thiophenes serve as valuable building blocks for materials chemistry, offering multiple reactive sites for further structural elaboration and property tuning.

Molbank doi: 10.3390/M2108

Authors: Andrea Marrero-González Juan F. Rodríguez-Caro María M. Afonso José Antonio Palenzuela

(S)-2-methyl-5-(prop-1-en-2-yl)cyclopent-1-ene-1-carbaldehyde (2) is a component of the essential oils of several plants and has also been used in many syntheses, usually of terpenes. Although the preparation of compound 2 has been reported several times, no side products have been reported previously. In this Short Note, we present the identification of one such side product. This new compound (3) arises from a vinylogous aldol autocondensation, occurring after the formation of 2, even when the reaction runs for a short time. However, it can diminish the yield of 2 when the reaction is allowed to continue for a longer time.

Molbank doi: 10.3390/M2107

Authors: Dan-Dan Xu Jie-Yi Ren Zhen-Ning Wu Yi-Yu Qi Jiang-Jiang Tang

1β, 6α-dihydroxy-5αH-eudesma-3(4), 11(13)-dien-12, 8β-olide is a natural eudesmane sesquiterpene lactone isolated from the aerial parts of Inula nervosa Wall. In this paper, we report the X-ray crystallography of the compound 1 for the first time, along with the 1D/2D NMR spectra.

Molbank doi: 10.3390/M2106

Authors: Roberto E. Blanco-Carapia Alejandro Islas-Jácome Eduardo González-Zamora

The multicomponent synthesis of a novel and highly symmetric polyheterocycle based on the pyrrolo[3,4-b]pyridin-5-one core incorporating the privileged tetrahydroisoquinoline moiety is described. The target compound was synthesized as an inseparable mixture of stereoisomers through a pseudo-repetitive Ugi–Zhu five-component reaction (PR-UZ-5CR) coupled to a double post-transformation sequence involving an intermolecular aza Diels–Alder cycloaddition, an intramolecular N-acylation, and a final tandem aromatization step. The product was prepared in 63% overall yield, and with an excellent atom economy of 85%, within a total reaction time of 85 min, and a temperature range from 25 to 65 °C. Structural elucidation and molecular mass confirmation were successfully achieved through NMR and FT-IR spectroscopy, and high-resolution mass spectrometry (HRMS), respectively.

Molbank doi: 10.3390/M2105

Authors: Anastasia A. Andreeva Yurii V. Shklyaev Andrey N. Maslivets

Compounds based on the pyrazoloquinazoline scaffold are of significant interest in synthetic organic chemistry owing to their potential biological activity. In this work, we describe the synthesis of a new derivative with this scaffold, 9-oxo-2-(p-tolyl)-4,9-dihydropyrazolo[5,1-b]quinazoline-3a(3H)-carboxylic acid, obtained by reacting 2,4-dioxo-4-(p-tolyl)butanoic acid with 2-aminobenzohydrazide in a 1:1 ratio when mixed in ethanol. The compound was characterized by 1H/13C NMR, IR, and X-ray diffraction analysis.

Molbank doi: 10.3390/M2104

Authors: Jaden K. Jones Aidan P. McKay David B. Cordes Brian A. Chalmers

We report the synthesis and molecular structure as determined by single-crystal X-ray diffraction of P,P,P′,P′-tetraisopropyl(1,4-phenylenebis(hydroxymethylene))bis(phosphonate). The compound was fully characterized by 1H, 13C, and 31P NMR spectroscopy, IR spectroscopy, and Mass Spectrometry.

Molbank doi: 10.3390/M2103

Authors: Agnieszka Maksymiuk-Kłos Rafał Słapa Marek Bartkowiak Radosław Michalik Monika Pazura-Turowska Dorota Szubińska-Lelonkiewicz Anna Bielenica

Substituted thiourea derivatives represent a structurally diverse group of compounds with high biological activity. In this paper, we present the synthesis of N-(9-ethyl-9H-carbazol-2-yl)-N′-(1-phenylethyl)thiourea by condensation reaction. The structure of the title compound was confirmed by 1H and 13C nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), and high-resolution mass spectrometry (HRMS).

Molbank doi: 10.3390/M2102

Authors: Daniil A. Bardonov Mikhail E. Minyaev Lada N. Puntus Ilya E. Nifant’ev Dmitrii M. Roitershtein

A new bis(cyclopentadienyl) terbium(III) complex with 1,2,4-triphenylcyclopentadienyl and 4,4,4-trifluoro-1-phenylbutane-1,3-dionate ligands was synthesized. Single-crystal X-ray analysis revealed a mononuclear bis(cyclopentadienyl) complex with a diketonate ligand in the bisector plane. The compound under study exhibits a ligand ligand charge transfer state (LLCT), according to optical spectroscopy and crystallographic data.

Molbank doi: 10.3390/M2101

Authors: Ilya P. Filippov Anastasiya V. Agafonova Nikolai V. Rostovskii Mikhail S. Novikov

The first representative of the aziridine-fused benzo[e][1,4]thiazine series was synthesized from methyl 2-bromo-2-phenyl-2H-azirine-2-carboxylate and benzo[d]thiazole in 74% yield. The reaction proceeds via the SN2′-SN2′-cascade to form the azirinylthiazolium salt followed by a water-induced thiazole ring expansion. The structure of the title compound was established based on 1H, 13C, 2D NMR spectroscopy and high-resolution mass spectrometry, and unambiguously confirmed by X-ray diffraction analysis.

Molbank doi: 10.3390/M2100

Authors: Saiya Yang Ya-Na Wang Yuyang Ma Ruirui Li Maxwell Ampomah-Wireko Cedric Dzidzor Kodjo Amengor En Zhang Yi-Hong Zhao

Structural optimization integrating triphenylamine and quaternary ammonium salt-based antimicrobial peptide mimics has yielded novel theranostic hybrid molecules. These compounds exhibit fluorescence imaging, photodynamic antibacterial activity, and membrane-disruption capabilities, demonstrating broad-spectrum efficacy with low resistance induction. In this study, we successfully developed a novel triphenylamine-quaternary ammonium derivative (TPQ), ultimately obtaining the target compound (E)-8-(4-(4-(diphenylamino)styryl)phenoxy)-N,N,N-trimethyloctan-1-aminium bromide (Compound 5). This achievement provides a potent strategy against growing bacterial drug resistance.

Molbank doi: 10.3390/M2099

Authors: Alexandra O. Derevnina Yurii V. Shklyaev Andrey N. Maslivets

The reaction of 5-(p-tolyl)furan-2,3-dione with thiourea in a 1:1 ratio when refluxed in 1,4-dioxane gives (Z)-N-carbamothioyl-4-hydroxy-2-oxo-4-(p-tolyl)but-3-enamide with a good yield. This compound was fully characterized.

Molbank doi: 10.3390/M2098

Authors: Jérôme Husson

Three new terpyridine derivatives which contain a pendant furan heterocycle have been prepared and characterized. The first two, 4′-(4,5-dimethylfuran-2-yl)-2,2′:6′,2″-terpyridine (1) and 4′-((1,3-dioxolan-2-yl)furan-2-yl)-2,2′:6′,2″-terpyridine (2), are obtained through the reaction of 2-acetylpyridine and suitable furaldehydes using the Kröhnke reaction. The last one, 4′-(5-formylfuran-2-yl)-2,2′:6′,2′’-terpyridine (3) is obtained via acidic hydrolysis of the acetal onto terpyridine (2). The structures of these new compounds are confirmed using different analytical techniques such as NMR and infrared spectroscopy (ATR-IR) as well as by High Resolution Mass Spectrometry (HRMS).

Molbank doi: 10.3390/M2097

Authors: Wiktoria Drzał Jarosław Sobstyl Nazar Trotsko

Heterocyclic systems such as 1,2,4-triazoles and piperazines play an important role in modern medicinal chemistry due to their structural diversity and broad spectrum of biological activities. In this Short Note, we report the synthesis and spectroscopic characterization of a new hybrid molecule combining both pharmacophoric fragments: 1-[4-(4-chlorophenyl)piperazin-1-yl]-2-[(4-phenyl-4H-1,2,4-triazol-3-yl)sulfanyl]ethan-1-one (compound 3). The compound was obtained in 70% yield via S-alkylation of 4-phenyl-1,2,4-triazole-3-thione with a chloroacetyl derivative of 4-chlorophenylpiperazine under alkaline conditions. The structure of 3 was confirmed by 1H and 13C NMR spectroscopy, DEPT-135, 2D NMR (COSY, NOESY, HSQC, HMBC), FT-IR, and elemental analysis. These results support the utility of combining triazole and piperazine fragments in the design of new heterocyclic frameworks with potential biological relevance.

Molbank doi: 10.3390/M2096

Authors: Dmitry V. Osipov Oleg P. Demidov Vitaly A. Osyanin

The reaction of a 2-naphthol-derived Mannich base with the push-pull 5-morpholinopenta-2,4-dienal under acidic conditions unexpectedly afforded (7aR*,7bR*)-7a,7b-dihydro-15H-dibenzo[f,f′]cyclopenta[1,2-b:5,4-b′]dichromene. The structure of this product was unambiguously confirmed by NMR spectroscopy and X-ray diffraction analysis. A plausible mechanism involves the in situ generation of 1,2-naphthoquinone-1-methide, followed by a [4 + 2] cycloaddition and a subsequent interrupted iso-Nazarov cyclization. In this process, the enol tautomer of the resulting fused cyclopentenone is trapped by a second equivalent of the 1,2-naphthoquinone-1-methide, leading to the observed polycyclic framework.

Molbank doi: 10.3390/M2095

Authors: Yordanka B. Ivanova Ognyan I. Petrov

In the present study, (E)-1-(2-(pyridin-2-yl)benzo[d]thiazol-6-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (4) was designed and synthesized via a three-step reaction sequence. Initially, 6-acetylbenzo[d]thiazol-2(3H)-one (1) was hydrolyzed to the corresponding 5-acetyl-2-aminothiophenol 2 and then cyclized with pyridine-2-carbaldehyde. The final product was synthesized by a base-catalyzed aldol condensation of 1-(2-(pyridin-2-yl)benzo[d]thiazol-6-yl)ethan-1-one (3) and 3,4,5-trimethoxybenzaldehyde and was comprehensively characterized.

Molbank doi: 10.3390/M2094

Authors: Petya Emilova Marinova Nikola Burdzhiev Evelina Varbanova Slava Tsoneva Stoyanka Nikolova

(This paper presents the synthesis of a novel copper(II) metal complex with ethyl (2-(methylcarbamoyl)phenyl)carbamate and 3-methylquinazoline-2,4(1H,3H)-dione. The characterization of the compound was conducted through various techniques, including melting point determination, microwave plasma atomic emission spectrometry (MP-AES) for Cu, attenuated total reflection (ATR), IR, 1H NMR, and 13C NMR spectroscopy. The coordination compound was obtained after mixing water solutions of the metal salt and the ligand dissolved in DMSO and water solutions of NaOH, in a metal-to-ligand-to-base ratio of 1:2:2. The ligand and the metal chloride were brought into the reaction at room temperature in DMSO and H2O as solvents, respectively. The results indicate the successful formation of a stable mixed-ligand Cu(II) coordination compound involving N,O-donor ligands. Based on the obtained data, we assumed that the ligands are coordinated through N- and O-donor atoms. Spectroscopic data suggested that the ligand (3-methylquinazoline-2,4(1H,3H)-dione), by using (NaOH), coordinated to a metal ion as a monodentate ligand through the nitrogen atom of the NH group and ethyl (2-(methylcarbamoyl)phenyl)carbamate coordinated in a bidentate fashion through the N- and O-donor atoms of ester group. Additionally, two hydroxyl groups were bridged for two metal ions into the formed dimer structure.

Molbank doi: 10.3390/M2093

Authors: R. Alan Aitken Hibet E. M. Akkache David B. Cordes Aidan P. McKay Dorian Moreau

The title compound has been fully characterised by NMR for the first time. Fully assigned 1H and 13C NMR spectra, and the X-ray structure of two different polymorphs are presented. The polymorphs show similar molecular geometries but exhibit significantly different patterns of intermolecular interactions.

Molbank doi: 10.3390/M2092

Authors: Jocelyn Pradegan Aurélien Crochet Katharina M. Fromm

A bimetallic complex based on a salophen-type ligand was synthesized. The compound was characterized by ESI-MS, single-crystal, and powder X-ray diffraction. The heterobimetallic complex was thermally treated to investigate its capacity as a single-source precursor for the formation of mixed metal oxides.

Molbank doi: 10.3390/M2091

Authors: Gulrukh Salieva Malokhat Uktamova Sardorbek Otajonov Kohei Torikai Tursunali Kholikov

2,5-Dimethylbenzyl 2-{(4,6-diaminopyrimidin-2-yl)thio}acetate was prepared by an alkylation reaction between the sodium salt of 4,6-diamino-2-mercaptopyrimidine and chloroacetic acid. The structure was unambiguously elucidated based on high-resolution mass spectrometry (HRMS) as well as spectroscopies such as infrared (IR) and nuclear magnetic resonance (NMR).

Molbank doi: 10.3390/M2090

Authors: Thamara V. Salazar-Barrientos Christopher P. Forfar Paul G. Hayes

A new zirconium trichloride complex, supported by a monoanionic, pyrrole-based bisphosphinimine NNN-pincer ligand, [LZrCl3] (L = 2,5-[iPr2P=N(4-iPrC6H4)]2NH(C6H2) (1), is reported. Comparison with a related iminopincer complex reveals significant differences in bond lengths and angles between the atoms around the metal centre, largely due to the more electron donating phosphinimine (R3P=NR (R = alkyl, aryl)) functionality. The P=N bonds in complex (1•benzene) are longer than in the proteo ligand HL (L = 2,5-[Ph2P=N(4-iPrC6H4)]2NH(C6H2)), which is consistent with phosphinimine coordination to a metal. This is the only reported zirconium complex with this specific ligand scaffold; no analogous complexes have been reported for other group 4 metals. This structure expands the library of Zr pincer complexes that bear tridentate ligand frameworks and sets the stage for the preparation of related complexes.

Molbank doi: 10.3390/M2089

Authors: R. Alan Aitken Rebecca Bascombe Alexandra M. Z. Slawin

The title compound has been fully characterised using 1H and 13C NMR spectroscopy, which reveals (E) to (Z) isomerisation upon dissolution. In the solid state, X-ray diffraction shows exclusively the (E)-isomer with two geometrically near-identical independent molecules each with the outer rings tilted with respect to the central ring.

Molbank doi: 10.3390/M2088

Authors: Alexandra V. Podturkina Nikolai S. Li-Zhulanov Tatyana V. Rybalova Konstantin P. Volcho Nariman F. Salakhutdinov

Parkinson’s disease (PD) is a progressive neurodegenerative disorder whose primary manifestation is motor dysfunction. Previous research showed that (1R,2R,6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol (Prottremine) exhibits potent antiparkinsonian activity in animal models of PD, with an efficacy comparable to levodopa. Herein, we report the synthesis of a new Prottremine derivative, (1R,2R,6S)-3-methyl-6-(3-(4-phenylpiperidin-1-yl)prop-1-en-2-yl)cyclohex-3-ene-1,2-diol. The compound was fully characterized and its structure was confirmed through single-crystal X-ray diffraction analysis.

Molbank doi: 10.3390/M2087

Authors: Yi-Qiong Sun Ya-Na Wang Kai-Wei Zhu Ruirui Li Maxwell Ampomah-Wireko Cedric Dzidzor Kodjo Amengor En Zhang Yi-Hong Zhao

Triphenylamine and phenol derivatives are two types of antimicrobial molecules with broad application prospects. Through functional modification, these compounds integrate fluorescence imaging and photodynamic antibacterial therapy, thereby achieving theranostic capabilities. They exert broad-spectrum and highly efficient antimicrobial activity via a membrane-disrupting mechanism, which consequently reduces the propensity for inducing drug resistance. In this work, triphenylamine-phenol derivatives (TPO) were designed and synthesized through three consecutive reactions: Wittig reaction, Heck reaction, and substitution reaction. Double bonds, hydroxyl groups, and brominated alkyl chains were gradually introduced to finally obtain the target product (E)-4-(4-((8-bromooctyl)oxy)styryl)-N,N-diphenylaniline (5). This study provides new insights into the development of novel and highly efficient antibacterial agents.

Molbank doi: 10.3390/M2086

Authors: Andrey Y. Chernenko Igor V. Lavrentev Maxim A. Shevchenko Mikhail E. Minyaev Konstantin E. Shepelenko Victor M. Chernyshev

Transition metal complexes bearing protic N-heterocyclic carbene (pNHC) ligands are promising precatalysts for organic reactions due to their capacity for unique hydrogen-bonding interactions. Herein, we report the synthesis and structural characterization of the first Pd(II) complex featuring a pNHC derived from 1,2,4-triazole—a heterocyclic system previously unexplored for the preparation of metal/pNHC complexes. The complex was synthesized via oxidative addition of 3-bromo-5-cyclohexyl-1-methyl-1H-1,2,4-triazole to Pd(PPh3)4 in the presence of NH4BF4. Its molecular structure was characterized by NMR spectroscopy and X-ray diffraction analysis.

Molbank doi: 10.3390/M2085

Authors: Zhong Guan James T. Slama

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a second messenger that stimulates intracellular Ca2+ release in both mammalian cells and echinoderm egg homogenates. A NAADP linked covalently to a stable long-wavelength fluorescent dye would be a useful probe with which to characterize NAADP–receptor interactions in solution and potentially to determine intracellular-binding localization. We report the synthesis of a BODIPY-NAADP covalent conjugate made through linking the carboxyl group of BODIPY FL to the primary amino group of 5-(3-aminopropyl)-NAADP through amide bond formation. The starting pyridine dinucleotide analog, 5-(3-aminopropyl)-NAADP was available through enzyme-catalyzed base exchange between NADP and a substituted nicotinic acid analog. The resulting 5-BODIPY-NAADP conjugate was purified to homogeneity using ion-exchange chromatography, was produced in milligram quantities, and its spectroscopic properties were characterized.

Molbank doi: 10.3390/M2083

Authors: Irina N. Meshcheryakova Ilya A. Yakushev Anton V. Cherkasov Maxim V. Arsenyev Anastasiya V. Klimashevskaya Dmitriy S. Kolevatov Alexandr V. Piskunov

Upon the reaction of glyoxal-bis(2-hydroxy-5-chlorophenyl)imine LH2 with diethyltin dichloride in the presence of a base (Et3N) in DMSO, the 1D-coordination polymer 1 was obtained, in which formally the L’(SnEt2)2 fragment acts as a monomeric unit. It was found that during the reaction, the initial ligand L undergoes transformation in the tin atom’s coordination sphere. This transformation results in the formation of a new ditopic 1,4-bis((5-chloro-2-oxidophenyl)imino)but-2-ene-2,3-bis(olate) ligand L’. The structure of the resulting complex 1 was examined by single-crystal X-ray diffraction analysis, elemental analysis, IR, and UV spectroscopy.

Molbank doi: 10.3390/M2084

Authors: Tamer S. Saleh Abdullah S. Al-Bogami

We report the first green and diastereoselective synthesis of novel thiophene bioisosteres designed to mimic the privileged pyrrolo[3,2-c]quinoline core of martinelline alkaloids. The key step features an intramolecular 1,3-dipolar cycloaddition of in situ generated non-stabilized azomethine ylides from sarcosine, which proceeds with excellent yield and diastereoselectivity. This sustainable protocol, leveraging ultrasonic irradiation, recyclable hydrotalcite catalysts, and the green solvent cyclopentyl methyl ether (CPME), efficiently constructs the complex tricyclic framework. The structure and stereochemistry of the novel bioisostere were unambiguously confirmed by X-ray crystallography. This method offers a valuable, eco-friendly approach for diversifying natural product-inspired libraries in medicinal chemistry.

Molbank doi: 10.3390/M2082

Authors: Dieter Schollmeyer Heiner Detert

The synthesis of the first 2-alkyl-1,2,3-selenadiazol-2-ium salt is reported. Extensive spectroscopic characterization including Se-NMR was performed and the results are compared with those of the known 3-ium isomer. The yellow compound crystallizes in blocks as well as in columns. The crystal structures of both types are solved by X-ray diffraction and give final proof of the molecular structure.

Molbank doi: 10.3390/M2081

Authors: Lesya Saliyeva Serhii Holota Nataliia Slyvka Mykhailo Vovk

Imidazothiazoles are important and attractive scaffolds for the design of potential biologically active small molecules. Dialkylenamines are convenient building blocks and are often used as intermediate reagents for the synthesis of various heterocyclic systems such as pyrimidine, pyridine, pyrazole, etc. In the present paper, the simple and effective synthesis of (Z)-6-((dimethylamino)methylene)-2-methyl-2,3-dihydroimidazo[2,1-b]thiazol-5(6H)-one (2) is reported. The proposed method, based on the reflux of 2-methyl-2,3-dihydroimidazo[2,1-b]thiazol-5(6H)-one with N,N-dimethylformamide dimethyl acetal, leads to an 80% yield of title compound 2. The structure of the synthesized compound 2 was confirmed using 1H, 13C NMR, and LC-MS spectra. The applied protocol demonstrates practical advantages such as the absence of a solvent, a simple work-up, and the possibility of scale-up.

Molbank doi: 10.3390/M2080

Authors: Roman V. Rumyantcev Marina A. Katkova Galina S. Zabrodina Georgy K. Fukin Sergey Yu. Ketkov

Recently, 3-hydroxy-4-pyridinones have been extensively studied as chelating bidentate agents of metal ions for various biomedical applications. This study reports the structural characterization and density functional theory (DFT) analysis of centrosymmetric calcium complex based on 4-(3-hydroxy-2-methyl-4-oxopyridin-1(4H)-yl) acetic acid (1). The structure of complex 1 was determined by X-ray crystallography. The 3-hydroxy-4-pyridinone ligand in the studied complex is bound to the calcium ion in the desired monodentate, non-bridging manner. The calcium ion has a coordination number of six and adopts a distorted octahedral geometry. Analyzed geometric characteristics corresponding to hydrogen bonds in the crystal. The theoretical study of intra- and intermolecular interactions utilized DFT with the PBE0-D3/def2-TZVP (Gaussian Inc., Wallingford, CT, USA) level of theory. The charge redistribution in the ligand was studied in comparison with the free acid molecule.

Molbank doi: 10.3390/M2079

Authors: Barbara Modec Nina Podjed Rihtaršič

Reactions of (pyH)5[MoOCl4(H2O)]3Cl2 with picolinic and pyrazinoic acids yielded three new dinuclear molybdenum(V) complexes: (pyH)2[Mo2O4Cl2(pic)2]·CH3CN (1), (pyH)2[Mo2O4Cl2(pic)2]·CH3CH2CN (2) and (pyH)2[Mo2O4Cl2(pyraz)2]·CH3CN (3) (pic− = picolinate, pyraz− = pyrazinoate and pyH+ = protonated pyridine). The compounds were characterized by single-crystal X-ray diffraction, infrared and 1H NMR spectroscopy, elemental analysis, and TG/DSC measurements. All display a robust {MoV2O4}2+ core with the heteroaromatic ligands bound in a N,O-bidentate chelating manner.

Molbank doi: 10.3390/M2078

Authors: Taylor Semeniuk Jean-Denys Hamel

Herein, the synthesis and crystallization of the unreported compound N-(2-fluoro-2-propen-1-yl)-5-(trifluoromethyl)-2-pyridinecarboxamide is achieved via amide coupling with a (2-fluoroallyl)ammonium salt. The structural properties are analyzed via single-crystal X-ray crystallography. Hydrogen bonding interactions between the amide groups and pyridine nitrogen atoms create a unique linear array of molecules in the crystal packing diagram. Furthermore, to validate the crystallographic data, the structural features of the compound are evaluated and compared to values reported in the literature.

Molbank doi: 10.3390/M2077

Authors: Francesco Bavo Christos Avgerinos Elena Martino Bente Frølund

Cyclic guanidines are valuable scaffolds for the design of compounds acting on GABAergic neurotransmission, owing to their ability to mimic the amino functionality of GABA as bioisosteres. With the aim to obtain a more potent and selective betaine/GABA transporter (BGT1) inhibitor, a basic hydrolysis of ethyl (E)-2-(acetylimino)-1-(3-phenylprop-2-yn-1-yl)hexahydropyrimidine-5-carboxylate was attempted. However, we isolated a byproduct, which was identified as the trifluoroacetate salt of 2-benzyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyrimidine-6-carboxylic acid. The structure was confirmed by NMR spectroscopy and LC-MS. Herein we report the preparation, characterization, and spectral data of this fused heterocyclic compound.

Molbank doi: 10.3390/M2076

Authors: Ichika Hayashida Malokhat Uktamova Sarvinoz Tirkasheva Kohei Torikai

Diols represent a structurally diverse class of compounds with considerable biological and functional significance. Herein, we describe the synthesis of 1,1-bis(4-ethylphenyl)propan-1,2-diol (BEPP) via a Grignard reaction. The structure of BEPP was unambiguously elucidated by 1H and 13C nuclear magnetic resonance (NMR), heteronuclear multiple-bond correlation (HMBC), high-resolution mass spectrometry (HRMS), and infrared (IR) spectroscopy.

Molbank doi: 10.3390/M2075

Authors: Dennis D. Toporkov Stacie K. Nelson Jean-Denys Hamel René T. Boeré

The compound 3-((benzyloxy)carbonyl)bicyclo[1.1.1]pentane-1-carboxylic acid was successfully synthesized. High-quality crystals were obtained, and its X-ray structure was solved and refined by Hirshfeld atom refinement using custom aspherical scattering factors with the Olex2/NoSphereA2 package. Hydrogen bonding interactions lead to head-to-head carboxylic acid dimer formation. A positional disorder for the bridging H-atom was detected and modeled to two parts in a 0.85:0.15 ratio. Detailed comparison with a neutron diffraction study of benzoic acid at the same temperature (100 K) demonstrates that the E–H-bond distances in the title compound are in excellent agreement (differing less than 1%) and the displacement ellipsoids volumes to the model are also in excellent agreement to the neutron diffraction structure. Moreover, both the variation in refined disorder occupancy and differences in C=O and C–O lengths of the disordered carboxylic acids in the two structures track well with their dimer O···O separations. This is longer by 0.023 Å in the structure of the title compound than in that of benzoic acid. A database search was conducted and used for comparison of the title compound to other high-quality structures of bicyclo[1.1.1]pentane-containing species.

Molbank doi: 10.3390/M2074

Authors: Roxana Ciorteanu Andreea Danila Catalina Ionica Ciobanu Ioana Radu Ionel I. Mangalagiu Ramona Danac

Six new unsymmetrical 7,7′-biindolizines were synthesized through an efficient metal-free [2+2+1] cycloaddition of ethyl 3-benzoyl-7-(pyridin-4-yl)indolizine-1-carboxylate with two equivalents of dimethyl acetylenedicarboxylate in methanol. The transformation involves one C≡C triple bond cleavage and provides access to previously unexplored unsymmetrical functionalized 7,7′-biindolizines.

Molbank doi: 10.3390/M2073

Authors: Michail N. Elinson Varvara M. Kalashnikova Yuliya E. Ryzhkova Oleg A. Rakitin

Cyclopropanes are important in drug discovery because their unique structure, including inherent three-dimensionality, can enhance a drug’s properties, such as metabolic stability, target binding, and membrane permeability. In this communication, (5R*,6R*) 11-benzoyl-4,10-dimethyl-2,8-diphenyl-2,3,8,9-tetraazadispiro[4.0.46.15]undeca-3,9-diene-1,7-dione was prepared via a stereoselective one-pot reaction of phenylglyoxal hydrate with two equivalents of 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one in EtOH in the presence of sodium acetate and N-bromosuccinimide. The structure of the newly synthesized compound was established by 1H and 13C NMR, IR spectroscopy, high-resolution mass spectrometry, and elemental analysis.

Molbank doi: 10.3390/M2072

Authors: Qinwei Xu Yuhan Xie Jin Qi Zimo Ren Carmine Coluccini Paolo Coghi

In this study, we report the synthesis of three new derivatives of betulinic acid, a pentacyclic triterpenoid known for its antitumor activity. These derivatives were synthesized via amide bond formation at the C-28 position using 3-[(Ethylimino)methylidene]amino-N,N-dimethylpropan-1-amine (EDC)/Hydroxybenzotriazole (HOBt) activation and various amines as nucleophiles. The synthesized compounds were characterized by nuclear magnetic resonance (NMR) techniques, including proton (1H), carbon-13 (13C), COSY, HSQC, and DEPT, as well as ultraviolet–visible (UV-VIS) spectroscopy, Fourier-transform infrared (IR) and elemental analysis. This work highlights the potential of semi-synthetic modification of betulinic acid to enhance anticancer properties while addressing challenges in solubility and bioavailability. Further structural optimization and formulation studies are warranted to improve drug-like properties and therapeutic applicability.

Molbank doi: 10.3390/M2071

Authors: Kyrill Yu. Suponitsky Akim V. Shmal’ko Sergey A. Anufriev Igor B. Sivaev

Crystal molecular structure of 3-(anthracen-2′-yl)-ortho-carborane was determined by single crystal X-ray diffraction study at 100 K. The asymmetric cell unit contains two enantiomeric pairs of molecules, in one of which the intramolecular dihydrogen bond CH...HB is formed with the participation of the C(1)H hydrogen of the anthracene substituent, and in the other with the participation of the C(3)H hydrogen. In all molecules, the polycyclic aromatic and carborane fragments are rotated relative to each other in such a way that the C-C bond of the ortho-carborane cage is approximately parallel to the plane of the aromatic substituent. According to quantum chemical calculations, the minimum energy corresponds to the formation of an intramolecular dihydrogen bond C(1)H...HB(4/7), whereas the C(3)H...HB(4/7) bond is formed rather as a result of intermolecular interactions in the crystal lattice.