4413-43-8

Developing novel fungicide candidates are intensively promoted by the rapid emergences of resistant fungi that outbreak on agricultural production. Aiming to discovery novel antifungal leads, a series of 1,3,4-oxadiazole derivatives bearing a quinazolin-4(3H)-one fragment were constructed for evaluating their inhibition effects against phytopathogenic fungi in vitro and in vivo. Systematically structural optimizations generated the bioactive molecule I32 that was identified as a promising inhibitor against Rhizoctonia solani with the in vivo preventative effect of 58.63% at 200 μg/mL. The observations that were captured by scanning electron microscopy and transmission electron microscopy demonstrated that the bioactive molecule I32 could induce the sprawling growth of hyphae, the local shrinkage and rupture on hyphal surfaces, the extreme swelling of vacuoles, the striking distortions on cell walls, and the reduction of mitochondria numbers. The above results provided an indispensable complement for the discovery of antifungal lead bearing a quinazolin-4(3H)-one and 1,3,4-oxadiazole fragment.

A series of novel 6-sulfonyl-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole derivatives were designed and synthesized. CoMFA models were established to analyze the quantitative structure-activity relationships on the basis of the EC50 values of the compounds. Th

A series of 3-[3-substituted-5-mercapto-1,2,4-triazol-4-yl]-spiro-(indan-1′,2-thiazolidin)-4-ones 2 were designed for the purpose of searching for novel antimicrobial agents and have been synthesized conveniently in a single step with a three-component protocol in polyethylene (400) as green reaction media. Thus, the condensation reaction between indane-1-one; 4-amino-5-mercapto-1,2,4-triazoles and mercaptoacetic acid in polyethylene glycol (400) gave quantitatively and analytically pure titled compounds 2. The structure of synthesized compound 2 is based on spectral (IR, 1H-NMR, and 13C-NMR) as well elemental analyses. These compounds have been screened for their antibacterial, antifungal, and antitubercular activities. Some of them have showed significant inhibition on fungal and bacterial growth and antitubercular activity against Mycobacterium tuberculosis. The compounds 2a, 2d, and 2e display antifungal activity against Candida albicans [minimum inhibitory concentration (MIC) 3.13, 6.25 μg/mL] and antibacterial activity against Streptococcus pneumoniae (MIC 3.13 μg/mL) of the order of standard drugs tested under similar conditions, and compound 2a showed better antitubercular activity than other compounds against M. tuberculosis (H37Rv strain, MIC 12.5 μg/mL).

Synthesis of a series of 7-arylidene-6-(2,4-dichlorophenyl)-3-aryloxymethyl/anilinomethyl-1,2,4-t riazolo[3,4-b]-1,3,4-thiadiazines (3) by the condensation of 3-aryl-1-(2,4-dichloro-5-fluorophenyl)-2-bromo-propen-1-one (1) and 4-amino-5-mercapto-3-aryloxy

3-Substituted-4-amino-5-mercapto-1,2,4-triazoles are versatile synthons for constructing various biologically active heterocycles. Their cyclization with carboxylic acids gives fused five-membered derivatives, whereas with α-bromoketones gives a six-membered heterocycle. In this article we report the synthesis of a series of 1,2,4-triazolo[3,4-b]thiadiazoles 5 starting from 4-amino-3-substituted-5-mercapto-1,2,4-triazoles 3 and fluorobenzoic acids 4 using phosphorous oxychloride as cyclizing agent. Fourteen of the newly synthesized compounds were screened for anticancer properties. Four among them showed in vitro anticancer activity.

Reactions of 3-aryloxymethyl-4-amino-5-mercapto-1,2,4-triazoles 1 with aromatic carboxylic acids, furoic acid, oxalic acid, monochloroacetic acid and phenacyl bromide furnish various N-bridged heterocycles viz., triazolothiadiazoles, bistriazolothiadiazoles, triazolothiadiazinones and triazolothiadiazines. The structures of these N-bridged heterocycles are characterized on the basis of elemental analyses, IR, NMR and mass spectral data. Some of these compounds are also subjected to antibacterial screening studies.

-

Seven 4-amino-3-aryloxymethyl-5-mercapto-1,2,4-triazoles (1a-g) have been synthesized and converted into 3-aryloxymethyl-4-(5-nitro-2-furfurylideneamino)-5-mercapto-1,2,4-triazoles (2a-g) and 7H-3-aryloxymethyl-6-(5-nitro-2-furyl)-s-triazolothiadiazines (3a-g).Most of the compounds of series 2 and 3 have been found to be active against both gram positive and gram negative bacteria at less than 5μg ml concentration.