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Molbank

Molbank is an international, peer-reviewed, open access journal comprised of a unique collection of one-compound-per-paper short notes on synthetic compounds and natural products published bimonthly online by MDPI.

Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
High Visibility: indexed within Scopus, ESCI (Web of Science), Reaxys, CAPlus / SciFinder, and other databases.
Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 12.7 days after submission; acceptance to publication is undertaken in 2.7 days (median values for papers published in this journal in the second half of 2025).
Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.

Impact Factor: 0.4 (2024)

Imprint Information Journal Flyer Open Access ISSN: 1422-8599

Latest Articles

8 pages, 987 KB

Open AccessCommunication

Crystal Structures of Two 4-Alkyl-8-hydroxyquinolines

by Sara Braun, Anke Schwarzer and Monika Mazik

Molbank 2026, 2026(3), M2176; https://doi.org/10.3390/M2176 (registering DOI) - 11 May 2026

4-Methyl- (1) and 4-ethyl-8-hydroxyquinoline (2) crystallize from a mixture of diethyl ether and chloroform in the triclinic space group P

\bar{1}

. X-ray analysis reveals that both compounds form discrete molecular dimers stabilized by intermolecular O-H∙∙∙N and C-H∙∙∙O [...] Read more.

4-Methyl- (1) and 4-ethyl-8-hydroxyquinoline (2) crystallize from a mixture of diethyl ether and chloroform in the triclinic space group P

\bar{1}

. X-ray analysis reveals that both compounds form discrete molecular dimers stabilized by intermolecular O-H∙∙∙N and C-H∙∙∙O hydrogen bonds, resulting in

R_{2}^{2} (5)

cyclic synthons. This pattern of hydrogen bonds is further stabilized by intramolecular O-H∙∙∙N bonds so that the quinoline nitrogen atom acts as a bifurcated binding site. The dimers exhibit a planar geometry and arrange into layer-like structures held together by π∙∙∙π stacking and van der Waals forces. While the fundamental bonding motifs are similar, the increased steric demand of the ethyl group in compound 2 induces a shift in the crystallographic orientation of the layers and alters the degree of π-overlap compared to the methyl-substituted analogue 1. Full article

(This article belongs to the Section Structure Determination)

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Graphical abstract

5 pages, 581 KB

Open AccessShort Note

2,2′-(Methylenebis(3,4-dimethoxy-6,1-phenylene))diacetic Acid

by Savina Stoyanova and Milen G. Bogdanov

Molbank 2026, 2026(3), M2177; https://doi.org/10.3390/M2177 (registering DOI) - 11 May 2026

The formation of side products is often unavoidable in organic synthesis; however, analyzing these secondary species provides practical insights into reaction pathways, mechanisms, and competing processes. This understanding is essential for optimizing reaction conditions, increasing product yields, and improving overall safety and efficiency. [...] Read more.

The formation of side products is often unavoidable in organic synthesis; however, analyzing these secondary species provides practical insights into reaction pathways, mechanisms, and competing processes. This understanding is essential for optimizing reaction conditions, increasing product yields, and improving overall safety and efficiency. Additionally, side products can sometimes reveal unexpected molecular structures with valuable properties. In this study, we present the characterization of a compound that formed as a side product in a modified Pictet-Spengler reaction. The molecular structure of 2,2′-(methylenebis(3,4-dimethoxy-6,1-phenylene))diacetic acid was elucidated using a combination of NMR, FTIR and UV–Vis spectroscopic techniques, as well as HRMS analysis. Full article

(This article belongs to the Collection Molecules from Side Reactions)

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6 pages, 428 KB

Open AccessCommunication

Formation of a β-(3-Chlorobenzoyloxy)-α-hydroxyketone from a TBS-Protected Chalcone upon Oxidation with m-Chloroperbenzoic Acid

by Sonia Berenguel-Gómez, Irene Moreno-Gutiérrez, Jenifer Acien-García, Manuel Muñoz-Dorado, Míriam Álvarez-Corral and Ignacio Rodríguez-García

Molbank 2026, 2026(3), M2175; https://doi.org/10.3390/M2175 (registering DOI) - 9 May 2026

A new tert-butyldimethylsilyl-protected polyoxygenated chalcone was prepared by Claisen–Schmidt condensation of suitably protected acetophenone and benzaldehyde derivatives. Treatment of this chalcone with m-chloroperbenzoic acid (mCPBA) afforded β-(3-chlorobenzoyloxy)-α-hydroxyketone 5, which was fully characterized by spectroscopic methods. The structure of 5 is consistent [...] Read more.

A new tert-butyldimethylsilyl-protected polyoxygenated chalcone was prepared by Claisen–Schmidt condensation of suitably protected acetophenone and benzaldehyde derivatives. Treatment of this chalcone with m-chloroperbenzoic acid (mCPBA) afforded β-(3-chlorobenzoyloxy)-α-hydroxyketone 5, which was fully characterized by spectroscopic methods. The structure of 5 is consistent with initial epoxidation of the enone double bond followed by in situ nucleophilic opening of the transient epoxide by m-chlorobenzoate generated in the reaction medium. This work reports the preparation of the chalcone precursor and the characterization of the unexpected oxidation product 5. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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Graphical abstract

4 pages, 1197 KB

Open AccessShort Note

N-(2,5-Difluorobenzylidene)-1-(2,5-difluorobenzyl)methanimine

by Tiffany L. Chen, Manisha Sharma and Nicholas E. Leadbeater

Molbank 2026, 2026(3), M2174; https://doi.org/10.3390/M2174 - 8 May 2026

The conversion of 2,5-difluorobenzylamine to N-(2,5-difluorobenzylidene)-1-(2,5-difluorobenzyl)methanimine using an oxoammonium salt bearing the nitrate anion is reported. The reaction is operationally simple, and the product is obtained with good yield. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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Graphical abstract

5 pages, 499 KB

Open AccessShort Note

(R)-10-((((2-(3,4-Dihydroxyphenyl)-2-hydroxyethyl)(methyl)carbamoyl)oxy)methyl)-1,3,5,5,7,9-hexamethyl-5H-dipyrrolo[1,2-c:2′,1′-f][1,3,2]diazaborinin-4-ium-5-uide

by Mikhail A. Panfilov, Alexey Yu. Vorob’ev and Alexander E. Moskalensky

Molbank 2026, 2026(3), M2173; https://doi.org/10.3390/M2173 - 7 May 2026

The BODIPY core has emerged as a versatile scaffold for the design of photoremovable protecting groups (PPGs). Herein, we report the synthesis of a novel BODIPY–epinephrine conjugate linked via a carbamate moiety, enabling light-triggered release of the active compound (epinephrine, also known as [...] Read more.

The BODIPY core has emerged as a versatile scaffold for the design of photoremovable protecting groups (PPGs). Herein, we report the synthesis of a novel BODIPY–epinephrine conjugate linked via a carbamate moiety, enabling light-triggered release of the active compound (epinephrine, also known as adrenaline). The structure of the obtained product was confirmed by ¹H and M ¹³C NMR spectroscopy as well as high-resolution mass spectrometry (HRMS). The described conjugate represents a potential tool for the photoactivated modulation of biologically relevant processes. Full article

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7 pages, 429 KB

Open AccessCommunication

Synthesis of (Z)-6-Heneicosen-11-one, a Possible Pheromone Component of the Hickory Tussock Moth, Lophocampa caryae

by Peter Mayo and Sumudu Deepa Abeysekera

Molbank 2026, 2026(3), M2171; https://doi.org/10.3390/M2171 - 6 May 2026

The compound (Z)-6-heneicosen-11-one, a possible pheromone component of the hickory tussock moth, Lophocampa caryae, and a known pheromone component of the Douglas fir tussock moth, Orgyia pseudotsugata, was synthesized by a new four-step procedure with a 39% overall yield [...] Read more.

The compound (Z)-6-heneicosen-11-one, a possible pheromone component of the hickory tussock moth, Lophocampa caryae, and a known pheromone component of the Douglas fir tussock moth, Orgyia pseudotsugata, was synthesized by a new four-step procedure with a 39% overall yield and a six-step procedure incorporating a protecting group with a 28% overall yield. This new synthesis is comparable to other similar syntheses for this molecule in the literature. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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6 pages, 378 KB

Open AccessShort Note

4-(6-Chloropyridin-3-yl)-6-cyclopropylpyrimidin-2-amine

by Yusen Wang, Jian Lv and Yukun Qin

Molbank 2026, 2026(3), M2172; https://doi.org/10.3390/M2172 - 6 May 2026

A novel nitrogen-containing heterocyclic compound, 4-(6-Chloropyridin-3-yl)-6-cyclopropylpyrimidin-2-amine, was designed and synthesized using 6-chloropyridin-3-aldehyde and cyclopropyl methyl ketone as starting materials. The structure of the target compound was characterized by ¹H NMR, ¹³C NMR and HRMS, and the spectral data were consistent with [...] Read more.

A novel nitrogen-containing heterocyclic compound, 4-(6-Chloropyridin-3-yl)-6-cyclopropylpyrimidin-2-amine, was designed and synthesized using 6-chloropyridin-3-aldehyde and cyclopropyl methyl ketone as starting materials. The structure of the target compound was characterized by ¹H NMR, ¹³C NMR and HRMS, and the spectral data were consistent with the expected structure, confirming the correctness of the product. Full article

(This article belongs to the Collection Heterocycle Reactions)

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10 pages, 662 KB

Open AccessCommunication

Synthesis of Three Bent Bis(imido-ferrocidiphenols)

by Pascal Pigeon

Molbank 2026, 2026(3), M2170; https://doi.org/10.3390/M2170 - 6 May 2026

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 [...] Read more.

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. Full article

(This article belongs to the Collection Heterocycle Reactions)

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Graphical abstract

9 pages, 1489 KB

Open AccessCommunication

New Pyridinium Salt Bioconjugates of Cholesterol and Methylpyridine Derivatives: Synthesis and Characterization

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

Molbank 2026, 2026(3), M2169; https://doi.org/10.3390/M2169 - 2 May 2026

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−¹ [...] Read more.

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). Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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8 pages, 991 KB

Open AccessCommunication

Synthesis of 2-(2-Methoxyphenyl)-4-methyl-6-nitroquinoline and 2-(2-Methoxyphenyl)-4-methylquinolin-6-amine

by Rumen Lyapchev, Maria Ivanova, Iskra Z. Koleva and Dimitar Shandurkov

Molbank 2026, 2026(3), M2168; https://doi.org/10.3390/M2168 - 30 Apr 2026

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. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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Graphical abstract

7 pages, 625 KB

Open AccessCommunication

Synthesis of (R)-(+)-3-(1-Hydroxyethylidene)-1-(1-phenylethyl)piperidine-2,4-dione, a Novel Tetramic Acid Analog

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

Molbank 2026, 2026(3), M2167; https://doi.org/10.3390/M2167 - 27 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Collection Heterocycle Reactions)

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Graphical abstract

6 pages, 350 KB

Open AccessCommunication

Synthesis of (S)-4-Benzyl-3-butyl-1-(2-cycloheptylethyl)imidazolidine

by Matevž Schweiger, Luka Ciber, Nejc Petek, Franc Požgan, Jurij Svete, Bogdan Štefane and Uroš Grošelj

Molbank 2026, 2026(2), M2166; https://doi.org/10.3390/M2166 - 16 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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8 pages, 2115 KB

Open AccessCommunication

A Bulky Aryl–Substituted Acridinium Salt: 10-(3,5-Di-tert-butylphenyl)-9-mesitylacridinium Tetrafluoroborate

by Yuki Itabashi and Kei Ohkubo

Molbank 2026, 2026(2), M2164; https://doi.org/10.3390/M2164 - 14 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Collection Molecules from Catalytic Processes)

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6 pages, 869 KB

Open AccessCommunication

Synthesis of 2-Aminonicotinonitriles via Photodecarboxylation of Azirine-2-Carboxylic Acids

by Julia I. Pavlenko, Mikhail S. Novikov and Anastasiya V. Agafonova

Molbank 2026, 2026(2), M2165; https://doi.org/10.3390/M2165 - 14 Apr 2026

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. [...] Read more.

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. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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6 pages, 470 KB

Open AccessCommunication

Synthesis of 2-Methylcamalexin

by Yordan Stremski, Maria Bachvarova, Stela Statkova-Abeghe and Plamen Angelov

Molbank 2026, 2026(2), M2163; https://doi.org/10.3390/M2163 - 13 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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8 pages, 797 KB

Open AccessShort Note

Racemic-Benzimidazolyl Pentafluorobenzyl Sulfoxide

by Maria Annunziata M. Capozzi and Cosimo Cardellicchio

Molbank 2026, 2026(2), M2161; https://doi.org/10.3390/M2161 - 10 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Section Structure Determination)

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4 pages, 428 KB

Open AccessShort Note

[2-{(5′-Amino-2′-fluoroacetophenone)-5-nitro}]acetophenone

by Richard M. Beteck and Lesetja J. Legoabe

Molbank 2026, 2026(2), M2162; https://doi.org/10.3390/M2162 - 10 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Collection Molecules from Side Reactions)

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10 pages, 1645 KB

Open AccessShort Note

1-Phenyl-4-p-tolyl-[1,2,3]triazole

by Eder Y. Nolasco-Terrón, David Gómez-Colín, Nelly González-Rivas, Diego Martínez-Otero and Erick Cuevas-Yañez

Molbank 2026, 2026(2), M2160; https://doi.org/10.3390/M2160 - 8 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Section Structure Determination)

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7 pages, 381 KB

Open AccessShort Note

Synthesis of a Calix[4]semitube with a Selectively Dinitrated Face

by Roderick Abdilla, Stefano Volpi, Alessandro Casnati, Maria A. Cardona and Ruben Gatt

Molbank 2026, 2026(2), M2159; https://doi.org/10.3390/M2159 - 7 Apr 2026

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 [...] Read more.

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. Full article

(This article belongs to the Section Organic Synthesis and Biosynthesis)

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4 pages, 407 KB

Open AccessShort Note

(+)-(3S)-8-(3-Methylbut-2-en-1-yl)-7-Methoxy-6,2′,4′-Trihydroxyisoflavan

by Hye Jin Kim, Kye Jung Shin, Khin Myo Htwe and Kee Dong Yoon

Molbank 2026, 2026(2), M2157; https://doi.org/10.3390/M2157 - 2 Apr 2026

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). Full article

(This article belongs to the Section Natural Product Chemistry)

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