Open AccessShort Note
Dichlorido(η6-p-cymene)[tris(2-cyanoethyl)phosphine]ruthenium(II)
Molbank 2018, 2018(4), M1025; https://doi.org/10.3390/M1025 -
Abstract
The tris(2-cyanoethyl)phosphine (tcep) complex [RuCl2{P(CH2CH2CN)3}(η6-p-cymene)] (p-cymene = p-CH3C6H4iPr) was synthesised by the bridge-splitting reaction of the chlorido-dimer [RuCl2(
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The tris(2-cyanoethyl)phosphine (tcep) complex [RuCl2{P(CH2CH2CN)3}(η6-p-cymene)] (p-cymene = p-CH3C6H4iPr) was synthesised by the bridge-splitting reaction of the chlorido-dimer [RuCl2(η6-p-cymene)]2 with tcep. The complex was characterised by a single-crystal X-ray structure determination as well as NMR spectroscopy, ESI mass spectrometry, and microelemental analysis. X-ray crystallography shows the ruthenium atom is coordinated by p-cymene in a η6-fashion, two chlorides and the phosphorus atom of the tcep ligand with the donor set defining a distorted octahedral geometry. The ESI mass spectrometry study reveals that the complex readily forms negative ions [M + Cl] and [2M + Cl] by association with a chloride ion. Full article
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Open AccessFeature PaperShort Note
2,3,4-Trioxo-1-(1H-pyrrolo[2,3-b]pyridin-7-ium-7yl)-cyclobutan-1-ide
Molbank 2018, 2018(4), M1026; https://doi.org/10.3390/M1026 -
Abstract
2,3,4-Trioxo-1-(1H-pyrrolo[2,3-b]pyridin-7-ium-7-yl)-cyclobutan-1-ide was obtained by reaction of squaric acid with 7-azaindole in acetic anhydride. Full article
Open AccessCommunication
Purine-Furan and Purine-Thiophene Conjugates
Molbank 2018, 2018(4), M1024; https://doi.org/10.3390/M1024 -
Abstract
Furyl and thienyl moieties were introduced into a purine structure to elevate its fluorescence properties, while a trityl group was used to increase the amorphous properties of the purine compounds. The title compounds were prepared by a sequence involving a Mitsunobu, a S
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Furyl and thienyl moieties were introduced into a purine structure to elevate its fluorescence properties, while a trityl group was used to increase the amorphous properties of the purine compounds. The title compounds were prepared by a sequence involving a Mitsunobu, a SNAr and a Suzuki–Miyaura reaction and their photophysical properties were studied. Quantum yields in the solution reached up to 88% but only up to 5% in the thin layer. Full article
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Open AccessCommunication
1-Methyl-3-{4-[(4-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)piperidin-1-yl)benzyl]}-2-phenylindole
Molbank 2018, 2018(4), M1023; https://doi.org/10.3390/M1023 -
Abstract
The 1-methyl-3-{4-[(4-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)piperidin-1-yl)benzyl]}-2-phenylindole compound has been successfully synthesized via a multistep pathway starting from 2-phenylindole. Structure characterization of this new indole derivative was done by FTIR, 1H-NMR, 13C-NMR, and HRMS spectral analysis. The title compound showed high cytotoxic potential against
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The 1-methyl-3-{4-[(4-(2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)piperidin-1-yl)benzyl]}-2-phenylindole compound has been successfully synthesized via a multistep pathway starting from 2-phenylindole. Structure characterization of this new indole derivative was done by FTIR, 1H-NMR, 13C-NMR, and HRMS spectral analysis. The title compound showed high cytotoxic potential against five leukemia cell lines (K562, HL60, U937, U266, and Jurkat cell lines). Full article
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Open AccessCommunication
Synthesis of 4-(2H-[1,2,4]-Triazol-5-ylsulfanyl)-1,2-dihydropyrazol-3-one via Ring-Switching Hydrazinolysis of 5-Ethoxymethylidenethiazolo [3,2-b][1,2,4]triazol-6-one
Molbank 2018, 2018(4), M1022; https://doi.org/10.3390/M1022 -
Abstract
4-(1H-[1,2,4]-Triazol-5-ylsulfanyl)-1,2-dihydropyrazol-3-one (4) was synthesized with a yield of 55% via ring-switching hydrazinolysis of 5-ethoxymethylidenethiazolo[3,2-b][1,2,4] triazol-6-one (3) in ethanol medium. The initial 1H-[1,2,4]-triazole-3-thiol (1) was modified via a two-step reaction: S-alkylation
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4-(1H-[1,2,4]-Triazol-5-ylsulfanyl)-1,2-dihydropyrazol-3-one (4) was synthesized with a yield of 55% via ring-switching hydrazinolysis of 5-ethoxymethylidenethiazolo[3,2-b][1,2,4] triazol-6-one (3) in ethanol medium. The initial 1H-[1,2,4]-triazole-3-thiol (1) was modified via a two-step reaction: S-alkylation with chloroacetic acid under Williamson reaction conditions, and further one-pot cyclization–condensation with triethylorthoformate in the acetic anhydride medium, yielding compound 3. The structures of compounds 3 and 4 were confirmed by LC-MS, NMR spectra and a single X-ray diffraction analysis (for compound 4). Full article
Open AccessShort Note
6-[1-Acetyl-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazole-3-yl]-2(3H)-benzoxazolone
Molbank 2018, 2018(4), M1021; https://doi.org/10.3390/M1021 -
Abstract
The title compound, 6-[1-acetyl-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl]-2(3H)-benzoxazolone, was synthesized by condensation of 6-[3-(4-methoxyphenyl)-2-propenoyl]-2(3H)-benzoxazolone (1) and hydrazine hydrate in acetic acid in 84% yield. The structure of the target compound was confirmed using 1H-NMR, 13C-NMR, IR, MS, and elemental analysis. Full article
Open AccessShort Note
O-Methyl m-Tolylcarbamothioate
Molbank 2018, 2018(3), M1020; https://doi.org/10.3390/M1020 -
Abstract
The synthesis, spectroscopic, and crystallographic characterisation of the title compound, O-methyl m-tolylcarbamothioate, MeOC(=S)N(H)(m-tolyl) (1), are described. The crystallographic study confirms the structure determined by spectroscopy and shows the presence of the thioamide tautomer, a syn-disposition of
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The synthesis, spectroscopic, and crystallographic characterisation of the title compound, O-methyl m-tolylcarbamothioate, MeOC(=S)N(H)(m-tolyl) (1), are described. The crystallographic study confirms the structure determined by spectroscopy and shows the presence of the thioamide tautomer, a syn-disposition of the thione-S and thioamide-N-H atoms and, in the crystal, thioamide-N-HS(thione) hydrogen bonding leading to an eight-membered {HNCS}2 synthon. Full article
Open AccessShort Note
(E)-1-(2′,4′-Dimethyl)-(5-acetylthiazole)-(2,4″-difluorophenyl)-prop-2-en-1-one
Molbank 2018, 2018(3), M1019; https://doi.org/10.3390/M1019 -
Abstract
Thiazole and chalcone motifs are of research interest to medicinal chemists due to their array of synthetic and biological utility. Hence, in the present study we intended to prepare (E)-1-(2′,4′-dimethyl)-(5-acetylthiazole)-(2,4″-difluorophenyl)-prop-2-en-1-one (3c) containing both these scaffolds. The compound 3c was
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Thiazole and chalcone motifs are of research interest to medicinal chemists due to their array of synthetic and biological utility. Hence, in the present study we intended to prepare (E)-1-(2′,4′-dimethyl)-(5-acetylthiazole)-(2,4″-difluorophenyl)-prop-2-en-1-one (3c) containing both these scaffolds. The compound 3c was synthesized by the acid-catalyzed condensation of 2,4-dimethyl-5-acetylthiazole with 2,4-difluorobenzaldehyde. Purification and characterization of the compound were carried out by recrystallization and spectral techniques including UV, IR, 1H-NMR, 13C-NMR, Mass spectrometry and X-ray powdered diffractometry. The molecule 3c was successfully synthesized, purified, and characterized. Full article
Open AccessFeature PaperShort Note
5-Amino-3-(diethylamino)-5H-benzo[4,5]imidazo[1,2-b][1,2,4,6]thiatriazine 1,1-Dioxide
Molbank 2018, 2018(3), M1018; https://doi.org/10.3390/M1018 -
Abstract
In the quest for discovery of novel bioactive molecules, new heterocyclic ring systems provide templates for exploration of uncharted chemical space. Herein, we describe the synthesis of a new benzo[4,5]imidazo[1,2-b][1,2,4,6]thiatriazine derivative from readily available 1,2-diaminobenzimidazole and N,N-diethyl-N
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In the quest for discovery of novel bioactive molecules, new heterocyclic ring systems provide templates for exploration of uncharted chemical space. Herein, we describe the synthesis of a new benzo[4,5]imidazo[1,2-b][1,2,4,6]thiatriazine derivative from readily available 1,2-diaminobenzimidazole and N,N-diethyl-N′-chlorosulfonyl chloroformamidine. The product structure, confirmed by X-ray crystallography, bears an exocyclic NH2 group, which should enable synthesis of an extended range of derivatives of this unusual scaffold. Full article
Open AccessFeature PaperShort Note
(S)-4-Isopropyl-5,5-diphenyloxazolidin-2-one
Molbank 2018, 2018(3), M1017; https://doi.org/10.3390/M1017 -
Abstract
(S)-4-Isopropyl-5,5-diphenyloxazolidin-2-one has been synthesized for the first time by the enantiospecific oxidative carbonylation of commercially available (S)-2-amino-3-methyl-1,1-diphenylbutan-1-ol. The cyclocarbonylation reaction was carried out at 100 °C in 1,2-dimethoxyethane (DME) as the solvent for 15 h, under 20 atm of
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(S)-4-Isopropyl-5,5-diphenyloxazolidin-2-one has been synthesized for the first time by the enantiospecific oxidative carbonylation of commercially available (S)-2-amino-3-methyl-1,1-diphenylbutan-1-ol. The cyclocarbonylation reaction was carried out at 100 °C in 1,2-dimethoxyethane (DME) as the solvent for 15 h, under 20 atm of a 4:1 mixture of CO–air and in the presence of the catalytic system PdI2/KI (substrate:KI:PdI2 molar ratio = 100:10:1), to give the oxazolidinone derivative in 81% isolated yield. Full article
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Open AccessShort Note
(1R,5S)-6-(4-Methyl-2-oxo-2,5-dihydrofuran-3-yl)-3-phenyl-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-en-7-one
Molbank 2018, 2018(3), M1016; https://doi.org/10.3390/M1016 -
Abstract
Efficient large-scale and feasible industrial synthesis of the 1-oxacephem core structure from 6-aminopenicillanic acid (6-APA) has been reported for several decades. Via the industrial synthesis route, a byproduct (compound 9) containing a butenolide unit was purified and characterized by NMR and HRMS
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Efficient large-scale and feasible industrial synthesis of the 1-oxacephem core structure from 6-aminopenicillanic acid (6-APA) has been reported for several decades. Via the industrial synthesis route, a byproduct (compound 9) containing a butenolide unit was purified and characterized by NMR and HRMS in this work. It is worth noting that compound 9 is an entirely new compound. Additionally, a plausible mechanism and effects on the formation of 9 by different Lewis acids were proposed. The discovery of compound 9 could improve the purity of this feasible industrial synthesis and provide considerable cost savings. Full article
Open AccessFeature PaperShort Note
(3-Ammonio-2,2-dimethyl-propyl)carbamate Dihydrate
Molbank 2018, 2018(3), M1015; https://doi.org/10.3390/M1015 -
Abstract
(3-Ammonio-2,2-dimethylpropyl)carbamate dihydrate was synthesised. The title compound was characterised by single crystal X-ray diffraction and IR-/Raman-spectroscopy. It has been demonstrated that a mixture of dilute acetic acid and 2,2-dimethyl-1,3-diaminopropane is able to capture CO2 spontaneously from the atmosphere. An intramolecular hydrogen bond
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(3-Ammonio-2,2-dimethylpropyl)carbamate dihydrate was synthesised. The title compound was characterised by single crystal X-ray diffraction and IR-/Raman-spectroscopy. It has been demonstrated that a mixture of dilute acetic acid and 2,2-dimethyl-1,3-diaminopropane is able to capture CO2 spontaneously from the atmosphere. An intramolecular hydrogen bond stabilises the conformation of the ylide-type title molecule. Intermolecular hydrogen bonds between all moieties connect them to a strand-type chain structure. Full article
Open AccessFeature PaperShort Note
1-[5-(4-Tolyl)-1,3,4-oxadiazol-2-yl]methanamine
Molbank 2018, 2018(3), M1014; https://doi.org/10.3390/M1014 -
Abstract
1-[5-(4-Tolyl)-1,3,4-oxadiazol-2-yl]methanamine (3) has been successfully synthesized by reacting p-toluic hydrazide (1) and glycine (2) via the polyphosphoric acid condensation route. The course of the reaction was found to be high yielding (87%) and the title compound
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1-[5-(4-Tolyl)-1,3,4-oxadiazol-2-yl]methanamine (3) has been successfully synthesized by reacting p-toluic hydrazide (1) and glycine (2) via the polyphosphoric acid condensation route. The course of the reaction was found to be high yielding (87%) and the title compound was spectroscopically characterized by UV-Vis, FTIR, DSC, 13C/1H-NMR, and sass spectrometric techniques. Full article
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Open AccessShort Note
5-[3-(4-Bromophenyl)-1-(2,5-dimethoxyphenyl)-3-oxopropyl]-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-tri-one
Molbank 2018, 2018(3), M1013; https://doi.org/10.3390/M1013 -
Abstract
The title compound was prepared by a two-step reaction. The first step was the formation of a chalcone derivative using Claisen–Schmidt condensation, which was followed by the Michael addition of the formed chalcone with 1,3-dimethylbarbituric acid. The structure of the prepared compound was
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The title compound was prepared by a two-step reaction. The first step was the formation of a chalcone derivative using Claisen–Schmidt condensation, which was followed by the Michael addition of the formed chalcone with 1,3-dimethylbarbituric acid. The structure of the prepared compound was established by spectral data: FTIR, HRESIMS, 1H- and 13C-NMR. Full article
Open AccessShort Note
N-(4-Bromophenyl)methoxycarbothioamide
Molbank 2018, 2018(3), M1012; https://doi.org/10.3390/M1012 -
Abstract
The synthesis, spectroscopic and crystallographic characterisation of the title compound, O-methyl-N-4-bromophenyl thiocarbamate, MeOC(=S)N(H)PhBr-4 (1), are described. Spectroscopy confirmed the formation of the compound and the molecular structure was determined crystallographically. Two independent but chemically similar molecules comprise the
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The synthesis, spectroscopic and crystallographic characterisation of the title compound, O-methyl-N-4-bromophenyl thiocarbamate, MeOC(=S)N(H)PhBr-4 (1), are described. Spectroscopy confirmed the formation of the compound and the molecular structure was determined crystallographically. Two independent but chemically similar molecules comprise the asymmetric unit of 1. The C‒S and C‒N bond lengths confirm the presence of the thioamide tautomer. The thione-S and amide-N‒H atoms are syn, enabling the formation of amide-N‒HS(thione) hydrogen bonds between the two independent molecules that generates a two-molecule aggregate via an eight-membered {HNCS}2 synthon. The aggregates are connected into a three-dimensional architecture via weak intermolecular interactions, including Brπ(4-bromophenyl), Sπ(4-bromophenyl), and weak BrS halogen bonding contacts. The overall molecular conformation, thioamide tautomer, and the presence of amide-N‒HS(thione) hydrogen bonding in the crystal conform with expectation for this class of compound. Full article
Open AccessShort Note
3-(3,5-Difluorophenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde
Molbank 2018, 2018(3), M1011; https://doi.org/10.3390/M1011 -
Abstract
Vilsmeier–Haack reaction of (E)-1-[1-(3,5-difluorophenyl)ethylidene]-2-phenylhydrazine (1) using dimethyl formamide in excess of phosphorus oxychloride by conventional method, resulted in the synthesis of the title compound 3-(3,5-difluorophenyl)-1-phenyl-1H-pyrazole-4- carbaldehyde (2) in good yield and high purity. Structure characterization
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Vilsmeier–Haack reaction of (E)-1-[1-(3,5-difluorophenyl)ethylidene]-2-phenylhydrazine (1) using dimethyl formamide in excess of phosphorus oxychloride by conventional method, resulted in the synthesis of the title compound 3-(3,5-difluorophenyl)-1-phenyl-1H-pyrazole-4- carbaldehyde (2) in good yield and high purity. Structure characterization of the title compound was done by IR, 1H-NMR, 13C-NMR and HRMS spectral analysis. Full article
Open AccessCommunication
Benzyl (R)-2-(Acetylthio)Propanoate: A Promising Sulfur Isoster of (R)-Lactic Acid and Ester Precursors
Molbank 2018, 2018(3), M1010; https://doi.org/10.3390/M1010 -
Abstract
In this paper, an accessible chiral pool synthesis of benzyl (R)-2-(acetylthio)propanoate (acetylthiolactate), which is less odorous than the methyl or ethyl analogue, was performed through a clean SN2 displacement reaction using available AcSK with tris[2-(2-methoxyethoxy)]ethylamine (TDA-1), starting from commercially
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In this paper, an accessible chiral pool synthesis of benzyl (R)-2-(acetylthio)propanoate (acetylthiolactate), which is less odorous than the methyl or ethyl analogue, was performed through a clean SN2 displacement reaction using available AcSK with tris[2-(2-methoxyethoxy)]ethylamine (TDA-1), starting from commercially available benzyl (S)-lactate in 76%, 94% ee (2 steps). Deprotection of the acetyl group using N,N-dimethylethylenediamine afforded benzyl (R)-2-sulfanylpropanoate in 93% yield with 90% ee. These two sulfur-containing benzyl esters were sufficiently odorless to be purified by column chromatography. Direct HPLC analysis was applied to determine the enantiomeric excess without thiazolidin-4-one derivatizations. A complementary debenzylation of benzyl (R)-2-(acetylthio)propanoate was also performed using HBr/AcOH to afford (R)-2-(acetylthio)propanoic acid without critical racemization in 92% yield with 92% ee. Full article
Open AccessShort Note
2-{[(4-Hydroxy-3,5-dimethoxyphenyl)methylidene]hydrazinylidene}-4-oxo-1,3-thiazolidin-5-yl Acetic Acid
Molbank 2018, 2018(3), M1009; https://doi.org/10.3390/M1009 -
Abstract
Thia-Michael addition of 2-[(4-hydroxy-3,5-dimethoxyphenyl)methylidene]hydrazine-1-carbothioamide (1) with maleic anhydride results in the formation of the title compound 2-{[(4-hydroxy-3,5-dimethoxyphenyl)methylidene]hydrazinylidene}-4-oxo-1,3-thiazolidin-5-yl acetic acid 2. The precursor 1 is synthesized by the reaction of 4-hydroxy-3,5-dimethoxybenzaldehyde and thiosemicarbazide in the presence of glacial acetic acid as
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Thia-Michael addition of 2-[(4-hydroxy-3,5-dimethoxyphenyl)methylidene]hydrazine-1-carbothioamide (1) with maleic anhydride results in the formation of the title compound 2-{[(4-hydroxy-3,5-dimethoxyphenyl)methylidene]hydrazinylidene}-4-oxo-1,3-thiazolidin-5-yl acetic acid 2. The precursor 1 is synthesized by the reaction of 4-hydroxy-3,5-dimethoxybenzaldehyde and thiosemicarbazide in the presence of glacial acetic acid as the catalyst. The structure of the title compound is determined by elemental analysis, FT-IR, 1H-NMR, 13C-NMR and mass spectral data. In order to determine the molecular interactions with the bacterial enzyme, the title compound is further docked into the active site of the MurB protein of Staphylococcus aureus (PDB ID: 1HSK). The in vitro antibacterial and antifungal activity of the title compound is carried out in order to appraise its antimicrobial efficacy by determination of zone of inhibition and minimal inhibitory concentration. The compound is also evaluated for its antioxidant property by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay. Full article
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Open AccessShort Note
N-[2-(1H-Indol-3-yl)-1-(5-thioxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)ethyl]-4-methylbenzenesulfonamide
Molbank 2018, 2018(3), M1008; https://doi.org/10.3390/M1008 -
Abstract
N-[1-Hydrazinyl-3-(1H-indol-3-yl)-1-oxopropan-2-yl]-4-methylbenzenesulfonamide (1) on cyclization with carbon disulfide in ethanolic potassium hydroxide affords N-[2-(1H-indol-3-yl)-1-(5-thioxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)ethyl]-4-methylbenzenesulfonamide (2) in 84% yield. The structure of compound 2 was supported by mass spectrometry, FT-IR and 1H- and 13
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N-[1-Hydrazinyl-3-(1H-indol-3-yl)-1-oxopropan-2-yl]-4-methylbenzenesulfonamide (1) on cyclization with carbon disulfide in ethanolic potassium hydroxide affords N-[2-(1H-indol-3-yl)-1-(5-thioxo-4,5-dihydro-1,3,4-oxadiazol-2-yl)ethyl]-4-methylbenzenesulfonamide (2) in 84% yield. The structure of compound 2 was supported by mass spectrometry, FT-IR and 1H- and 13C-NMR spectroscopy. To investigate the potential of compound 2 to act as antitubercular agent, it was docked against the enoyl reductase (InhA) enzyme of Mycobacterium tuberculosis. The docking pose and non-covalent interactions gave insights on its plausible inhibitory action. Full article
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Open AccessShort Note
5,7-Dihydroxy-3,6-Dimethoxy-3′,4′-Methylendioxyflavone
Molbank 2018, 2018(3), M1007; https://doi.org/10.3390/M1007 -
Abstract
A new flavonoid derivative, namely 5,7-dihydroxy-3,6-dimethoxy-3′,4′-methylenedioxyflavone (1), was isolated from the leaves of Melicope glabra (Blume) T.G. Hartley. The structure of 1 was elucidated based on their UV, IR, HRESIMS, and 1D and 2D NMR spectral data. Full article