Synthesis and antimicrobial activity of substituted [(pyrazol‐4‐yl)methylene]hydrazono‐2,3‐dihydrothiazoles and their sugar derivatives

Abstract

A number of new [(pyrazol-4-yl)methylene]hydrazono-2,3-dihydrothiazole derivatives, their sugar hydrazones and N-glycosides were synthesized. Furthermore, N-substituted oxygenated alkyl and hydroxyl derivatives and 1,3,4,-oxadiazoline acyclic nucleoside analogs were prepared. The newly synthesized compounds were tested for their antimicrobial activities and showed moderate to high inhibition activities.

Synthesis, computational and biological evaluation of some new pyridine Derivatives

“…al. reported the synthesis of many heterocycles from enaminones as starting material [23]. Many pyridine derivatives were reported from our lab [24,25].…”

Synthesis, computational and antimicrobial evaluation of some new pyridine derivatives

“…The 1 HNMR showed chemical shifts at δ 2.95 and 3.18 ppm as singlet signals due to two CH 3 groups, doublets at δ 5.66 and 7.68 ppm due to two CH protons, in addition to, doublets at δ 7.85 and 8.70 ppm corresponding to pyridine (AB system). Furthermore, a molecular ion peak at m/z = 176 appeared in its mass spectrum due to the chemical formula C 10 H 12 N 2 O. Fadda et al [ 23 ] reported the synthesis of many heterocycles from enaminones as starting material. Many pyridine derivatives were reported from our lab.…”

Synthesis, Characterization and in vitro Cytotoxic Evaluation of Some Novel Heterocyclic Compounds Bearing Indole Ring

“…Therefore, the initial monoacetyl-substituted products are gradually converted to diacetyl substituted thiadiazoline 10 4.1H-NMR spectrum of compound 4 showed a signal at δ 2.16, δ 2.19, δ 2.26 ppm corresponding to three CH 3 groups and multiplet signal at δ 6.93-7.28 ppm for the aromatic protons and CH-5 of1,3,4-thiadiazoline ring. The mass spectrum of compound 4 showed the molecular ion peak at m/z 547 corresponding to the molecular formula C 27 H 23 Br N 4 O 2 S. Furthermore, treatment of thiosemicarbazone derivative 2a with phenacyl bromides in boiling ethanol in the presence of anhydrous sodium acetate 11 yielded the corresponding 3-[1,3-thiazol-2(3H)-ylidene]hydrazonomethyl-1H-indole derivative 5.1H-NMR spectrum of 5 showed a signal at δ 6.58 ppm corresponding to CH-5 of thiazole ring and signal at δ 8.30 ppm for an N=CH proton .The mass spectrum of compound 5 showed the molecular ion peak at m/z 563 corresponding to the molecular formula C 31 H 23 BrN 4 S. Refluxing thiosemicarbazone derivative 2a with chloroacetic acid in the presence of anhydrous sodium acetate in glacial acetic acid 12 afforded 1,3-thiazolidin-4-one derivative 6 (Scheme 1). IR spectra of 6 showed the disappearance of NH bands of substituted thiosemicarbazone moiety and the presence of a new band at 1703 cm −1 attributed to a carbonyl group of thiazolidin-4-one.…”