Antiulcer agents. II. Synthesis and gastric acid antisecretory activity of N-[3-(3-(piperidinomethyl)phenoxy)propyl]-4-(1-methyl-1H- tetrazol-5-ylthio)butanamide and related compounds

Synthesis, anticandidal activity and cytotoxicity of some tetrazole derivatives

In this study, 14 different 2-[(1-methyl-1H-tetrazole-5-yl)thio]-1-(phenyl)ethanone derivatives (1-14) were synthesized. The structures of the obtained compounds were elucidated using IR, (1)H-NMR, (13)C-NMR and FAB(+)-MS spectral data and elemental analyses results. The compounds were screened for their anticandidal activity using the microbroth dilution method and for their cytotoxic effects using the MTT assay against NIH/3T3 cells. Some of the compounds were found to be potent anticandidal agents with weak cytotoxicities.

1-Alkyl-5-((di)alkylamino) tetrazoles: building blocks for peptide surrogates

An approach to the synthesis of 1-alkyl-5-((di)alkylamino)tetrazoles by nucleophilic substitution in 1-alkyl-5-sulfonyltetrazoles with anions generated from the primary or secondary amines was developed. Tolerance of the method to the presence of some functional groups (i.e., protected amine) in both components of the reaction was demonstrated. Obtained tetrazoles are promising building blocks for the design of peptide surrogates, in particular, for replacement approaches of alkyl urea derivatives.

Isotopic effect on tautomeric behavior of 5-(2,6-disubstituted-aryloxy)-tetrazoles

Isotopic effect on tautomeric behaviors of the synthesized 5-phenoxy- (1a), 5-(2,6-dimethylphenoxy)-(1b), 5-(2,6-diisopropylphenoxy)-(1c), 5-(2,6-dimethoxyphenoxy)-(1d) and 5-(4-methylphenoxy)-tetrazole (1e) were investigated in DMSO-d6 by adding one drop of D2O. Among 1a-e, 1a, 1d and 1e show small rotational barrier around C5-O1 and O1-C6 while in 1b and 1c there are distinguishable rotational barrier about that bonds. The (1)H NMR spectra of 1b and 1c show slightly different chemical shifts for two methyl and isopropyl groups on those phenyl ring, respectively, while the chemical shifts difference (Δδ) between two methyl and two isopropyl groups were enhanced by adding D2O. The (13)C NMR spectra of 1b show two overlapped singlets for methyl groups after adding D2O. Representatively, the calculations of compound 1c were performed with GAUSSIAN-03 and the rotational barrier about C5-O1 and between isopropyl group and phenyl ring in 1c was calculated with B3LYP/6-31G(d) basis set.

Synthesis and antinociceptive activity of some substituted-{5-[2-(1,2,3,4-tetrahydrocarbazol-9-yl)ethyl]tetrazol-1-yl}alkanones

Twelve different derivatives of substituted-{5-[2-(1,2,3,4-tetrahydrocarbazol-9-yl)ethyl]tetrazol-1-yl}alkanones (3-14) were synthesized by reacting 9-[2-(1H-tetrazol-5-yl)-ethyl]-2,3,4,9-tetrahydro-1H-carbazole (2) and the appropriate acid chlorides. 9-[2-(1H-tetrazol-5-yl) ethyl]-2,3,4,9-tetrahydro-1H-carbazole (2) was synthesized by reacting 3-(1,2,3,4-tetrahydrocarbazol-9-yl) propionitrile (1) with sodium azide and ammonium chloride. The chemical structures were confirmed by means of IR, 1H-NMR, mass spectra and elemental analysis. The compounds were screened for antinociceptive activity by acetic acid induced writhing method and hot plate method. 1-Phenyl-2-{5-[2-(1,2,3,4-tetrahydrocarbazol-9-yl)ethyl]tetrazol-1-yl}ethanone (13) was found to be the most active compound of the series.

Synthesis and analgesic evaluation of some 5-[β-(10-phenothiazinyl)ethyl]-1-(acyl)-1,2,3,4-tetrazoles

A series of novel 5[beta-(phenothiazinyl-10-yl)ethyl]-1-(acyl)-1,2,3,4-tetrazoles (3-14) have been synthesized via condensation of 5-[beta-(phenothiazinyl-10-yl)ethyl]-1-2,3,4-tetrazole (2) with various acylating/sulphonating reagents. 5-[beta-(phenothiazinyl-10-yl)ethyl]-1-2,3,4-tetrazole was synthesized by cyanoethylation of phenothiazine with acrylonitrile and Triton B, followed by the cycloaddition of 3-(phenothiazin-10-yl)-propionitrile (1) with sodium azide and ammonium chloride. The compounds were screened for analgesic activity, anti-inflammatory activity and ulcerogenicity index. Out of the 12 compounds synthesized, compound (5) 5[beta-(phenothiazinyl-10-yl)ethyl]-1-(benzoyl)-1,2,3,4-tetrazole, compound (11) 5[beta-(phenothiazinyl-10-yl)ethyl]-1-(p-tolyl)-1,2,3,4-tetrazole showed promising analgesic activity and compound (6) 5[beta-(phenothiazinyl-10-yl)ethyl]-1-(p-chlorobenzoyl)-1,2,3,4-tetrazole and compound (8) 5[beta-(phenothiazinyl-10-yl)ethyl]-1-(p-nitrobenzoyl)-1,2,3,4-tetrazole showed promising anti-inflammatory activity.