Previous Issue
Volume 2026, June
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
0.9
0.3
Journals
Molbank
Volume 2026
Issue 4
share announcement

Molbank, Volume 2026, Issue 4 (August 2026) – 22 articles

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
7 pages, 796 KB  
Short Note
(1E,4E)-1,5-Bis(2,4-dichlorophenyl)penta-1,4-dien-3-one Oxime
by Juan P. Montaño, Andres F. Sánchez and Rodrigo Abonia
Molbank 2026, 2026(4), M2215; https://doi.org/10.3390/M2215 - 6 Aug 2026
Viewed by 14
Abstract
The target (1E,4E)-1,5-bis(2,4-dichlorophenyl)penta-1,4-dien-3-one oxime 4 was prepared in good yield, as a key aza-precursor for the Nazarov cyclization, through a two-step sequence in this study. Initially, the starting divinyl ketone 1a was obtained via a Claisen–Schmidt condensation reaction between [...] Read more.
The target (1E,4E)-1,5-bis(2,4-dichlorophenyl)penta-1,4-dien-3-one oxime 4 was prepared in good yield, as a key aza-precursor for the Nazarov cyclization, through a two-step sequence in this study. Initially, the starting divinyl ketone 1a was obtained via a Claisen–Schmidt condensation reaction between 2,4-dichlorobenzaldehyde 3 and acetone in the presence of aqueous 20% NaOH. Subsequently, treating 1a with hydroxylamine hydrochloride under thermal conditions resulted in the expected oxime in excellent yield, and its structure was confirmed by analytic and spectroscopic techniques. Full article
►▼ Show Figures

Figure 1

4 pages, 336 KB  
Short Note
Bis([1,2,5]thiadiazolo)[3,4-f:3′,4′-h]quinoxaline-8,9-dicarbonitrile
by Anastasiya S. Yushkova, Ekaterina A. Knyazeva and Oleg A. Rakitin
Molbank 2026, 2026(4), M2214; https://doi.org/10.3390/M2214 - 4 Aug 2026
Viewed by 128
Abstract
Compounds containing electron-withdrawing dicyanopyrazine and 1,2,5-chalcogenadiazole fragments are promising for the design of magnetic and optoelectronic materials. In this paper, bis([1,2,5]thiadiazolo)[3,4-f:3′,4′-h]quinoxaline-8,9-dicarbonitrile was prepared via Körner–Hinsberg condensation of benzo[1,2-c:3,4-c′]bis([1,2,5]thiadiazole)-4,5-dione with 2,3-diaminomaleonitrile in the presence of catalytic amounts of TsOH in refluxing ethanol. The structure [...] Read more.
Compounds containing electron-withdrawing dicyanopyrazine and 1,2,5-chalcogenadiazole fragments are promising for the design of magnetic and optoelectronic materials. In this paper, bis([1,2,5]thiadiazolo)[3,4-f:3′,4′-h]quinoxaline-8,9-dicarbonitrile was prepared via Körner–Hinsberg condensation of benzo[1,2-c:3,4-c′]bis([1,2,5]thiadiazole)-4,5-dione with 2,3-diaminomaleonitrile in the presence of catalytic amounts of TsOH in refluxing ethanol. The structure of the newly synthesized compound was established via elemental analysis, mass spectrometry, 13C NMR, and IR spectroscopy. Full article
►▼ Show Figures

Graphical abstract

7 pages, 517 KB  
Short Note
Methyl 6-(2,3-Dimethoxybenzamido)-2,3-dihydroxybenzoate
by Guo-Li Li, Zhi-Dong Yu, Na Gao, Hong-Ying Yang, Yi-Lin He and Tong Shen
Molbank 2026, 2026(4), M2213; https://doi.org/10.3390/M2213 - 4 Aug 2026
Viewed by 102
Abstract
Gymnaconitum gymnandrum, a Tibetan medicinal herb, is distributed across high-altitude regions of China. Despite its high toxicity, it exhibits analgesic, anti-inflammatory, antitumor, and other pharmacological activities. It is used topically for skin conditions and orally for rheumatism. Its main bioactive components are [...] Read more.
Gymnaconitum gymnandrum, a Tibetan medicinal herb, is distributed across high-altitude regions of China. Despite its high toxicity, it exhibits analgesic, anti-inflammatory, antitumor, and other pharmacological activities. It is used topically for skin conditions and orally for rheumatism. Its main bioactive components are alkaloids. A new organic amine alkaloid has been isolated from the plant and structurally identified using HRMS, NMR, and X-ray diffraction. Full article
(This article belongs to the Section Natural Product Chemistry)
►▼ Show Figures

Figure 1

5 pages, 326 KB  
Short Note
(Z)-3′-(3-Chloro-4-fluorophenyl)-5-fluoro-5′-((6-methoxypyridin-3-yl)methylene)spiro[indoline-3,2′-thiazolidine]-2,4′-dione
by Dominika Kuceł, Jarosław Sobstyl, Serhii Holota and Dmytro Khylyuk
Molbank 2026, 2026(4), M2212; https://doi.org/10.3390/M2212 - 4 Aug 2026
Viewed by 119
Abstract
A novel spiro[indoline-3,2′-thiazolidine]-2,4′-dione derivative incorporating 3-chloro-4-fluorophenyl and 6-methoxypyridin-3-yl fragments was synthesized and characterized. The synthetic route involved a two-step procedure, including the preparation of the spirocyclic scaffold via cyclocondensation of 5-fluoroisatin with 3-chloro-4-fluoroaniline in the presence of mercaptoacetic acid, followed by Knoevenagel condensation [...] Read more.
A novel spiro[indoline-3,2′-thiazolidine]-2,4′-dione derivative incorporating 3-chloro-4-fluorophenyl and 6-methoxypyridin-3-yl fragments was synthesized and characterized. The synthetic route involved a two-step procedure, including the preparation of the spirocyclic scaffold via cyclocondensation of 5-fluoroisatin with 3-chloro-4-fluoroaniline in the presence of mercaptoacetic acid, followed by Knoevenagel condensation with 6-methoxypyridine-3-carbaldehyde. The reactions were carried out under reflux conditions and afforded the desired product in a satisfactory yield after purification by recrystallization. The structure of the synthesized compound was confirmed by 1H and 13C NMR spectroscopy, LC–MS analysis, FT-IR and elemental analysis, all of which were consistent with the proposed molecular structure. The presence of multiple pharmacologically relevant heterocyclic motifs within a single framework suggests that this compound may serve as a useful scaffold for further biological evaluation. Full article
►▼ Show Figures

Scheme 1

11 pages, 3119 KB  
Communication
N-Demethyl-N-nitrosolevofloxacin
by Claudio Maestri, Mattia Lopresti, Ivana Miletto, Attila Benyei, Marzia Petreti, Luisa Zangirolami, Camilla Cavallotti and Giovanni B. Giovenzana
Molbank 2026, 2026(4), M2211; https://doi.org/10.3390/M2211 - 4 Aug 2026
Viewed by 135
Abstract
Levofloxacin is an antibiotic belonging to the fluoroquinolone family. N-Demethyllevofloxacin, a metabolite and an impurity of levofloxacin, features a secondary amine that is susceptible to N-nitrosation, raising concerns about the formation of a potentially toxic nitrosamine. The corresponding N-nitrosamine was [...] Read more.
Levofloxacin is an antibiotic belonging to the fluoroquinolone family. N-Demethyllevofloxacin, a metabolite and an impurity of levofloxacin, features a secondary amine that is susceptible to N-nitrosation, raising concerns about the formation of a potentially toxic nitrosamine. The corresponding N-nitrosamine was synthesized in two steps and characterized using HRMS, NMR spectroscopy, IR spectroscopy, UV absorption and emission spectroscopies and powder X-ray diffraction. This work provides a reliable reference for the quantitation and control of nitrosamine impurities associated with levofloxacin in chemical and pharmaceutical contexts. Full article
►▼ Show Figures

Graphical abstract

7 pages, 970 KB  
Short Note
N4-Benzoyl-N3-benzyl-2′-deoxycytidine
by Andrea Patrizia Falanga, Maria Marzano and Stefano D’Errico
Molbank 2026, 2026(4), M2210; https://doi.org/10.3390/M2210 - 3 Aug 2026
Viewed by 148
Abstract
We have recently demonstrated that the pendant tert-butyldiphenylsilyl (TBDPS) groups in the short oligonucleotides TBDPS-5′-CG-3′-3′-GC-5′-TBDPS and TBDPS-5′-CGG-3′-3′-GGC-5′-TBDPS promoted the formation of new lipophilic and stable tetramolecular G-quadruplexes (GQs). Encouraged by these findings, we sought to investigate the effect of alternative lipophilic substituents [...] Read more.
We have recently demonstrated that the pendant tert-butyldiphenylsilyl (TBDPS) groups in the short oligonucleotides TBDPS-5′-CG-3′-3′-GC-5′-TBDPS and TBDPS-5′-CGG-3′-3′-GGC-5′-TBDPS promoted the formation of new lipophilic and stable tetramolecular G-quadruplexes (GQs). Encouraged by these findings, we sought to investigate the effect of alternative lipophilic substituents at the flanking cytidine residues on GQ formation and properties. Herein, we reported on the synthesis and spectroscopic characterization of the new N4-benzoyl-N3-benzyl-2′-deoxycytidine, which was obtained during our attempts to synthesize N4-benzoyl-5′-O-benzyl-2′-deoxycytidine. Full article
(This article belongs to the Collection Molecules from Side Reactions)
►▼ Show Figures

Graphical abstract

9 pages, 1942 KB  
Communication
A New Bis(8-hydroxyquinolinylmethyl) Perhydrobenzimidazole Obtained from a Cyclic Aminal Derived from trans-1,2-Diaminocyclohexane and 8-Hydroxyquinoline
by Augusto Rivera, Jaime Ríos-Motta and Diego Quiroga
Molbank 2026, 2026(4), M2209; https://doi.org/10.3390/M2209 - 3 Aug 2026
Viewed by 135
Abstract
The reaction of 8-hydroxyquinoline and (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo [8.8.1.1.8,170.2,70.11,16]icosane under Mannich-type conditions afforded a new quinoline-functionalized diazabicyclic derivative in 27% yield. The structure of the product was established by FT-IR, 1H and 13C NMR, HSQC, HMBC, and [...] Read more.
The reaction of 8-hydroxyquinoline and (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo [8.8.1.1.8,170.2,70.11,16]icosane under Mannich-type conditions afforded a new quinoline-functionalized diazabicyclic derivative in 27% yield. The structure of the product was established by FT-IR, 1H and 13C NMR, HSQC, HMBC, and ESI-MS analyses, which confirmed the connectivity between the two quinoline units and the perhydrobenzimidazole heterocyclic fragment. The conformational strain of the perhydroimidazolidine fragment prevents the rearrangement pathway previously reported for related systems, such as cyclic aminal 1,3,6,8-tetraazatricyclo [4.4.1.13,8]dodecane (TATD), leading to a different reaction outcome. The results demonstrate that the conformationally constrained aminal exhibits reactivity distinct from that reported for TATD-derived systems, providing new insight into the behavior of cyclic aminals in Mannich-type reactions. Full article
(This article belongs to the Collection Heterocycle Reactions)
►▼ Show Figures

Figure 1

2 pages, 147 KB  
Correction
Correction: Pasdar et al. Eco-Friendly Synthesis of Perimidine Derivatives Using Recyclable Fe3O4@Nano-Cellulose/Ti(IV). Molbank 2026, 2026, M2181
by Ghaffar Pasdar, Abdolhamid Bamoniri and Bi Bi Fatemeh Mirjalili
Molbank 2026, 2026(4), M2208; https://doi.org/10.3390/M2208 - 3 Aug 2026
Viewed by 66
Abstract
In the original publication [...] Full article
(This article belongs to the Collection Heterocycle Reactions)
6 pages, 4709 KB  
Short Note
Synthesis and X-Ray Characterization of a New 1,2-Dichloroethane Solvate of 5,10,15,20-Tetraphenylporphyrin-21,23-Diium Dichloride
by Domenica Marabello, Paola Benzi and Elena Cariati
Molbank 2026, 2026(4), M2207; https://doi.org/10.3390/M2207 - 30 Jul 2026
Viewed by 161
Abstract
1,2-Dichloroethane was found to stabilize the lattice of chloride anions associated with the protonated porphyrin of formula [C44H32N4]Cl2·4C2H4Cl2. The synthesis and X-ray characterization of this compound are reported and [...] Read more.
1,2-Dichloroethane was found to stabilize the lattice of chloride anions associated with the protonated porphyrin of formula [C44H32N4]Cl2·4C2H4Cl2. The synthesis and X-ray characterization of this compound are reported and compared with analogous solvates. The porphyrin macrocycle displays a distorted saddle conformation, with chloride anions positioned above and below the mean plane of the ring, further surrounded by two dichloroethane molecules that stabilize the crystal packing. The Second-Harmonic Generation response was evaluated using the Kurtz–Perry powder technique with a ND:YAG laser (1064 nm). Full article
(This article belongs to the Section Structure Determination)
►▼ Show Figures

Figure 1

5 pages, 482 KB  
Short Note
(4aS,5R,6aS,7R,11aS,11bR)-9-(1-Benzyl-1H-benzo[d]imidazol-2-yl)-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl Acetate
by Jessica A. Perez-Rangel, Alejandro Islas-Jácome, Luis Chacón-García, Armando Talavera-Alemán and Carlos J. Cortés-García
Molbank 2026, 2026(4), M2206; https://doi.org/10.3390/M2206 - 17 Jul 2026
Viewed by 388
Abstract
A new benzimidazole–6β-acetoxyvouacapane (4aS,5R,6aS,7R,11aS,11bR)-9-(1-benzyl-1H-benzo[d]imidazol-2-yl)-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl acetate was synthesized through the semisynthetic functionalization of the natural product 6β-acetoxyvouacapane. The target compound was obtained via a liquid-assisted mechanochemical condensation of [...] Read more.
A new benzimidazole–6β-acetoxyvouacapane (4aS,5R,6aS,7R,11aS,11bR)-9-(1-benzyl-1H-benzo[d]imidazol-2-yl)-4,4,7,11b-tetramethyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodecahydrophenanthro[3,2-b]furan-5-yl acetate was synthesized through the semisynthetic functionalization of the natural product 6β-acetoxyvouacapane. The target compound was obtained via a liquid-assisted mechanochemical condensation of aldehyde 6β-acetoxyvouacapane with N-benzyl-o-phenylenediamine, followed by cyclization and oxidative aromatization under mild reaction conditions. The structure of the new compound was established by FT-IR, 1D and 2D NMR spectroscopy (COSY, HSQC, and HMBC), and high-resolution mass spectrometry (HRMS). Full article
(This article belongs to the Section Natural Product Chemistry)
►▼ Show Figures

Graphical abstract

4 pages, 406 KB  
Short Note
1,5,9-tri(Phenylethynyl)-4,8,12-trioxaphosphangulene
by Kimiya Sukegawa, Masaki Yamamura and Tatsuya Nabeshima
Molbank 2026, 2026(4), M2205; https://doi.org/10.3390/M2205 - 16 Jul 2026
Viewed by 298
Abstract
4,8,12-Trioxaphosphangulene is a bowl-shaped phosphorus-containing π-conjugated molecule whose molecular geometry is highly sensitive to the substituent attached to the phosphorus atom. Herein, we report the synthesis of a new tungsten pentacarbonyl complex of a chiral 4,8,12-trioxaphosphangulene bearing three phenylethynyl groups. The complex was [...] Read more.
4,8,12-Trioxaphosphangulene is a bowl-shaped phosphorus-containing π-conjugated molecule whose molecular geometry is highly sensitive to the substituent attached to the phosphorus atom. Herein, we report the synthesis of a new tungsten pentacarbonyl complex of a chiral 4,8,12-trioxaphosphangulene bearing three phenylethynyl groups. The complex was prepared by coordination of the phosphine center to an in situ generated W(CO)5 fragment and was characterized by multinuclear NMR spectroscopy and elemental analysis. The NMR spectra revealed that the phosphangulene framework retains its threefold symmetry in solution. Comparison of the NMR parameters with those of a previously reported phosphangulene–tungsten complex indicates that incorporation of the phenylethynyl substituents has little effect on either the coordination environment around the phosphorus atom or the phosphine–tungsten interaction. These findings demonstrate that the characteristic bowl-shaped phosphangulene framework is preserved upon tungsten coordination despite π-extension of the molecular framework. Full article
(This article belongs to the Section Structure Determination)
►▼ Show Figures

Figure 1

6 pages, 358 KB  
Communication
Synthesis of Azirinylammonium Salts via Alkylation of DABCO with 2-Halo-2H-azirines
by Maksim A. Valiarovskii, Alexander V. Vorob’ev, Anastasiya V. Agafonova and Mikhail S. Novikov
Molbank 2026, 2026(4), M2204; https://doi.org/10.3390/M2204 - 14 Jul 2026
Viewed by 282
Abstract
Tertiary (2H-azirin-2-yl)ammonium salts were prepared from methyl 2-halo-3-aryl-2H-azirine-2-carboxylates and 1,4-diazabicyclo[2.2.2]octane in very good to excellent yields. Both iodide and bromide salts are stable enough in crystalline form to be stored in a freezer for up to several months. The [...] Read more.
Tertiary (2H-azirin-2-yl)ammonium salts were prepared from methyl 2-halo-3-aryl-2H-azirine-2-carboxylates and 1,4-diazabicyclo[2.2.2]octane in very good to excellent yields. Both iodide and bromide salts are stable enough in crystalline form to be stored in a freezer for up to several months. The structures of the obtained salts were confirmed by NMR spectroscopy and HRMS. Full article
(This article belongs to the Section Organic Synthesis and Biosynthesis)
►▼ Show Figures

Graphical abstract

9 pages, 1489 KB  
Short Note
10-(3,5-Di-tert-butylphenyl)-9-methylacridinium Tetrafluoroborate
by Yuki Itabashi and Kei Ohkubo
Molbank 2026, 2026(4), M2203; https://doi.org/10.3390/M2203 - 14 Jul 2026
Viewed by 355
Abstract
A 9-methylacridinium salt, 10-(3,5-di-tert-butylphenyl)-9-methylacridin-10-ium tetrafluoroborate (2), was synthesized from the corresponding acridone by treatment with methylmagnesium bromide followed by tetrafluoroboric acid. Compound 2 was obtained as a yellow solid in 95% yield and characterized by NMR spectroscopy and high-resolution [...] Read more.
A 9-methylacridinium salt, 10-(3,5-di-tert-butylphenyl)-9-methylacridin-10-ium tetrafluoroborate (2), was synthesized from the corresponding acridone by treatment with methylmagnesium bromide followed by tetrafluoroboric acid. Compound 2 was obtained as a yellow solid in 95% yield and characterized by NMR spectroscopy and high-resolution mass spectrometry. Electrochemical measurements revealed irreversible reduction behavior, with a reduction potential of −0.52 V vs. SCE determined by second-harmonic alternating-current voltammetry. Compound 2 exhibited absorption extending into the visible region and fluorescence at 492 nm with a lifetime of 4.6 ns. Unlike the previously reported 9-mesityl analogue, compound 2 was fluorescent, a difference that may reflect the absence of the high-lying donor orbital associated with the 9-mesityl group. Its singlet excited-state reduction potential was estimated to be +2.21 V vs. SCE, indicating substantial photooxidizing ability. DFT and TD-DFT calculations provided complementary insight into its frontier molecular orbital distributions and principal electronic transitions. These findings highlight the influence of the 9-substituent on the electronic and emissive properties of acridinium-based photoactive molecules. Full article
(This article belongs to the Collection Molecules from Catalytic Processes)
►▼ Show Figures

Figure 1

8 pages, 2161 KB  
Short Note
(5S)-5-[(2-(5-Bromo-2-methoxyphenyl)quinazolin-4-yl Amino)methyl]-3-(3-fluoro-4-morpholinophenyl)oxazolidin-2-one
by Mingguang Zhang, Siyu Hao, Baiyang Mao and Yongxu Piao
Molbank 2026, 2026(4), M2202; https://doi.org/10.3390/M2202 - 10 Jul 2026
Viewed by 388
Abstract
4-aminoquinazoline derivatives exhibit unique physiological activities, including antitumor, anti-inflammatory, and antibacterial biological activities. Afatinib (BIBW-2992), the representative tyrosine kinase inhibitor, has been developed for the treatment of non-small cell lung cancer. Following our expanded medical chemistry research program, we report a novel 4-aminoquinazoline [...] Read more.
4-aminoquinazoline derivatives exhibit unique physiological activities, including antitumor, anti-inflammatory, and antibacterial biological activities. Afatinib (BIBW-2992), the representative tyrosine kinase inhibitor, has been developed for the treatment of non-small cell lung cancer. Following our expanded medical chemistry research program, we report a novel 4-aminoquinazoline derivative named JSLN-P (1), (5S)-5-[(2-(5-bromo-2-methoxyphenyl) quinazolin-4-ylamino)methyl]-3-(3-fluoro-4-morpholino phenyl) oxazolidin-2-one, aimed for developing new drugs with antiglioma properties. The title compound JSLN-P (1) was successfully synthesized by amination approaches following benzylamination and oxazolone cyclization, further condensation with 4-(4-bromo-2-fluorophenyl) morpholine, reduction in debenzylation and halogenated amination of quinazolin. The structure of JSLN-P (1) was confirmed by 1H and 13C nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Full article
(This article belongs to the Section Organic Synthesis and Biosynthesis)
►▼ Show Figures

Figure 1

4 pages, 234 KB  
Short Note
(E)-4-(3-Oxo-3-(2-oxo-2,3-dihydrobenzo[d]oxazol-6-yl)prop-1-en-1-yl)benzaldehyde
by Yordanka B. Ivanova, Daniel Y. Yordanov and Ognyan I. Petrov
Molbank 2026, 2026(4), M2201; https://doi.org/10.3390/M2201 - 9 Jul 2026
Viewed by 224
Abstract
In the present study, (E)-4-(3-oxo-3-(2-oxo-2,3-dihydrobenzo[d]oxazol-6-yl)prop-1-en-1-yl)benzaldehyde (2) was synthesized via a base-catalyzed Claisen–Schmidt condensation of 6-acetylbenzo[d]oxazol-2(3H)-one (1) and terephthalaldehyde and characterized by spectroscopic methods. Full article
►▼ Show Figures

Scheme 1

5 pages, 569 KB  
Short Note
N-(4-fluorobenzyl)-N′-(4-fluorobenzylidene)-4-methylbenzenesulfonohydrazide
by Lei Gao, Li Xu, Zheng Zhang, Jinchang Zhang, Diangang Bai, Xiangrong Wang and Yue Zhang
Molbank 2026, 2026(4), M2200; https://doi.org/10.3390/M2200 - 6 Jul 2026
Viewed by 246
Abstract
Herein, we present the synthesis of N-(4-fluorobenzyl)-N’-(4-fluorobenzylidene)-4-methylbenzenesulfonohydrazide. The compound has been thoroughly characterized through melting-point determination, 1H and 13C NMR spectroscopy and mass spectrometry. The structure was unequivocally determined by X-ray analysis. The comprehensive analytical data obtained from [...] Read more.
Herein, we present the synthesis of N-(4-fluorobenzyl)-N’-(4-fluorobenzylidene)-4-methylbenzenesulfonohydrazide. The compound has been thoroughly characterized through melting-point determination, 1H and 13C NMR spectroscopy and mass spectrometry. The structure was unequivocally determined by X-ray analysis. The comprehensive analytical data obtained from these techniques confirm the successful preparation and structural integrity of the newly synthesized molecule. Full article
►▼ Show Figures

Figure 1

7 pages, 1974 KB  
Short Note
Methyl 3-(Propan-2-ylidene)-3a,9a-dihydro-3H-cyclopenta[a]azulene-9-carboxylate
by Miku Yoshida, Masafumi Yasunami, Ryuta Sekiguchi, Shunji Ito and Taku Shoji
Molbank 2026, 2026(4), M2199; https://doi.org/10.3390/M2199 - 3 Jul 2026
Viewed by 287
Abstract
Methyl 3-(propan-2-ylidene)-3a,9a-dihydro-3H-cyclopenta[a]azulene-9-carboxylate (2) was synthesized in moderate yield via an [8 + 2] cycloaddition of methyl 2-oxo-2H-cyclohepta[b]furan-3-carboxylate (1) with 6,6-dimethylfulvene. The resulting compound was characterized by 1H and 13C NMR spectroscopy, high-resolution mass spectrometry, and single-crystal X-ray diffraction analysis. Full article
(This article belongs to the Section Structure Determination)
►▼ Show Figures

Figure 1

8 pages, 2007 KB  
Communication
Synthesis of 8-Bromo-2-(chloromethyl)-6-methoxy-5-nitroimidazo[1,2-a]pyridine and 8-Bromo-2-(chloromethyl)-6-methoxy-3,5-dinitroimidazo[1,2-a]pyridine
by Inès Jacquet, Romain Paoli-Lombardo, Caroline Castera-Ducros, Patrice Vanelle and Nicolas Primas
Molbank 2026, 2026(4), M2198; https://doi.org/10.3390/M2198 - 3 Jul 2026
Viewed by 269
Abstract
A novel synthetic approach was developed to synthesize 6-methoxy substituted imidazo[1,2-a]pyridine derivatives, with the objective of obtaining analogs of previously identified antileishmanial hit compounds. The nitration of 8-bromo-2-(chloromethyl)-6-methoxyimidazo[1,2-a]pyridine under classical nitric acid/sulfuric acid conditions resulted in selective nitration at [...] Read more.
A novel synthetic approach was developed to synthesize 6-methoxy substituted imidazo[1,2-a]pyridine derivatives, with the objective of obtaining analogs of previously identified antileishmanial hit compounds. The nitration of 8-bromo-2-(chloromethyl)-6-methoxyimidazo[1,2-a]pyridine under classical nitric acid/sulfuric acid conditions resulted in selective nitration at position 5 and the corresponding 3,5-dinitrated derivative. The structures of these compounds were established through a combination of experimental methods, including 1H and 13C NMR, HRMS, HSQC, and HMBC experiments. These structural determinations were subsequently confirmed through single-crystal X-ray diffraction. These compounds represent the first examples of 5-nitrated and 3,5-dinitrated 6-methoxyimidazo[1,2-a]pyridines. Full article
►▼ Show Figures

Figure 1

6 pages, 459 KB  
Short Note
Olean-18α-19β,28-epoxy-3β-benzoate
by Xiqiang Gao, Jung Hoon Park, Bohua Lu, Jinxing Zhai, Xiaoyi Sun, Yuanhui Wang, Lak Shin Jeong and Qiang Wang
Molbank 2026, 2026(4), M2197; https://doi.org/10.3390/M2197 - 1 Jul 2026
Viewed by 288
Abstract
Allobetulin 3-benzoate was obtained as an unexpected byproduct during the acid-mediated protection–deprotection of betulin. Single-crystal X-ray diffraction analysis shows that it crystallizes in the triclinic space group P1 with Z = 2 and contains two crystallographically independent molecules in the asymmetric unit. [...] Read more.
Allobetulin 3-benzoate was obtained as an unexpected byproduct during the acid-mediated protection–deprotection of betulin. Single-crystal X-ray diffraction analysis shows that it crystallizes in the triclinic space group P1 with Z = 2 and contains two crystallographically independent molecules in the asymmetric unit. Compared with allobetulin (P21, Z = 4) and allobetulin 3-acetate (C2, Z = 4), the benzoyl substitution at C-3 induces distinct molecular packing and intermolecular interaction patterns, highlighting the influence of steric and electronic effects on crystal architecture. Full article
►▼ Show Figures

Figure 1

9 pages, 1149 KB  
Communication
The Crystal Structure of N,N′-bis(3,5-di-tert-Butylsalicylidene)propane-1,2-diamine)-oxidovanadium(IV) and Its Parent Ligand
by Kirsten S. Graham, Aidan P. McKay, David B. Cordes and Brian A. Chalmers
Molbank 2026, 2026(4), M2196; https://doi.org/10.3390/M2196 - 1 Jul 2026
Viewed by 305
Abstract
The asymmetric salen ligand N,N′-bis(3,5-di-tert-butylsalicylidene)propane-1,2-diamine (1) with a single chiral center and its vanadyl complex (2) have been prepared and characterized by single-crystal X-ray diffraction. Full article
(This article belongs to the Section Structure Determination)
►▼ Show Figures

Figure 1

8 pages, 1494 KB  
Short Note
3-(4-Hydroxynaphthalen-1-yl)-3-(1-hydroxynaphthalen-2-yl)isobenzofuran-1(3H)-one
by Brian A. Chalmers, David B. Cordes, Tomas Lebl, Aidan P. McKay, Iain L. J. Patterson, Nadiia Vladymyrova and Iain A. Smellie
Molbank 2026, 2026(4), M2195; https://doi.org/10.3390/M2195 - 1 Jul 2026
Viewed by 289
Abstract
3-(4-hydroxynaphthalen-1-yl)-3-(1-hydroxynaphthalen-2-yl)isobenzofuran-1(3H)-one is a previously unknown derivative of the well-known acid/base indicator naphtholphthalein. We report the synthesis and the molecular structure of the title compound, as determined by single-crystal X-ray diffraction. 1H and 13C NMR spectroscopy data, IR spectroscopy data, [...] Read more.
3-(4-hydroxynaphthalen-1-yl)-3-(1-hydroxynaphthalen-2-yl)isobenzofuran-1(3H)-one is a previously unknown derivative of the well-known acid/base indicator naphtholphthalein. We report the synthesis and the molecular structure of the title compound, as determined by single-crystal X-ray diffraction. 1H and 13C NMR spectroscopy data, IR spectroscopy data, and mass spectrometry data are provided. Full article
(This article belongs to the Section Structure Determination)
►▼ Show Figures

Figure 1

7 pages, 477 KB  
Short Note
Methyl (S)-3-((1r*,3R*)-3-((1H-indol-3-yl)methyl)cyclobutane-1-carboxamido)-2-(phenylsulfonamido)propanoate
by Helen M. Sheldrake
Molbank 2026, 2026(4), M2194; https://doi.org/10.3390/M2194 - 1 Jul 2026
Viewed by 314
Abstract
The cyclobutane ring has attractive properties as a scaffold in medicinal chemistry but is underused, potentially due to the limited methods available for synthesising highly functionalised cyclobutanes. This short note describes the synthesis of the 1,3-cis disubstituted cyclobutane, methyl (S)-3-((1 [...] Read more.
The cyclobutane ring has attractive properties as a scaffold in medicinal chemistry but is underused, potentially due to the limited methods available for synthesising highly functionalised cyclobutanes. This short note describes the synthesis of the 1,3-cis disubstituted cyclobutane, methyl (S)-3-((1r*,3R*)-3-((1H-indol-3-yl)methyl)cyclobutane-1-carboxamido)-2-(phenylsulfonamido)propanoate using a one-pot thermal stepwise cycloaddition reaction and its characterisation by NMR spectroscopy and HRMS. Full article
(This article belongs to the Section Organic Synthesis and Biosynthesis)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-22
Previous Issue
Back to TopTop