1,3-Dipolar Cycloaddition Reactions in Heterocyclic Synthesis. Synthesis of [1-[4-(thiazolyl/imidazothiazolyl/triazolyl)phenyl]-1H-pyrazole-3,4-dicarboxylate esters from 3-(4-acetylphenyl)sydnone

Cycloaddition of 3-(4-acetylphenyl)sydnone (1) with DMAD gave dimethyl 1-(4-acetylphenyl)-1H-pyrazole-3,4-dicarboxylate (2), which on bromination yielded the corresponding monobromoacetyl (3) and dibromoacetyl (4) derivatives. Both compounds 3 and 4 on reaction with thiourea and thioacetamide afforded the 2-amino- (5) and the 2-methyl- (6) thiazole derivatives respectively, while compound 3 on reaction with 2-aminothiazole gave the imidazothiazole 7. Compound 3 was converted into its azide (8), which on 1,3-dipolar cycloaddition with DMAD afforded the 1,2,3-triazole-4,5-dicarboxylate (9).

Synthesis and Biological Activities of Some Schiff's Bases from 4-amino-3-(3-hydroxybutyl)-1H-1, 2, 4-triazole-5-thione

Sixteen novel Schiff's bases have been synthesised in high yields from 4-amino-3-(3-hydroxybutyl)-1 H-1, 2, 4-triazole-5-thione. All the newly synthesised compounds have been characterised by elemental analysis, IR, 1H NMR, 13C NMR and MS. Plant growth-regulating activity tests showed that most compounds have remarkable effects on the growth of wheat and radish at a mass concentration of 50μg mL−1.

New sulphonamide and carboxamide derivatives of acyclic C-nucleosides of triazolo-thiadiazole and the thiadiazine analogues. Synthesis, anti-HIV, and antitumor activities. Part 2

A new series of acyclic C-nucleosides 1',2'-O-isopropylidene-D-ribo-tetritol-1-yl)[1,2,4] triazolo[3,4-b][1,3,4]thiadiazoles bearing arylsulfonamide (5-8) and arylcarboxamide (9-12) residues have been synthesized under microwave irradiation. Thiadiazines 13-15 have been analogously prepared, and upon acid hydrolysis, afforded the free nucleosides 16-18. The new synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. Compound 7 was also screened against a panel of tumor cell lines consisting of CD4 human T-cells.

Synthesis and biological activity of some novel derivatives of 4-amino-3-(D-galactopentitol-1-yl)-5-mercapto-1,2,4-triazole

To discover new 1,2,4-triazole derivatives which may possess significant biological activities, we synthesized a series of novel 6-aryl-3-(D-galactopentitol-1-yl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines and 4-(arylmethylidene)amino-5-(D-galactopentitol-1-yl)-3-mercapto-4H-1,2,4-triazoles from 4-amino-3-(D-galactopentitol-1-yl)-5-mercapto-1,2,4-triazole. All the title compounds were characterized by elemental analysis, IR, 1H- and 13C-NMR. Plant growth-regulating activity tests showed that these compounds have remarkable effects on the growth of radish and wheat.

Synthesis and biological evaluation of some novel Schiff's bases from 1,2,4-triazole

We have synthesized a number of novel Schiff's bases from 4-amino-3-(D-glucoheptonic-hexitol-1-yl)-1H-1,2,4-triazole-5-thione. By attaching D-glucoheptonic-hexitol-1-yl residues to 1,2,4-triazole at the 3-position, the solubility of the title compounds has been improved greatly. All the products have been characterized by elemental analysis, IR, 1H-NMR, 13C-NMR and MS. The plant-growth regulating effects of the title compounds were examined. From the biological activity results, we found that most compounds showed weak to moderate activities.

Syntheses and biological activities of 6-aryl-3-(3-hydroxypropyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines

A series of 6-aryl-3-(3-hydroxypropyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]-thiadiazines were synthesized by the reaction of 4-amino-3-(3-hydroxypropyl)-5-mercapto-1,2,4-triazole (1) with substituted omega-haloacetophenones. Their structures were confirmed by elemental analysis, IR, 1H-NMR, and 13C-NMR. Tests of plant growth regulating effects showed that the title compounds display remarkable inhibitory activities on the growth of radish and wheat.