Convenient diastereoselective synthesis of annulated 3-substituted-(5S*,6S*,Z)-2-(2-(2,4-dinitrophenyl)hydrazono)-5,6-diphenyl-1,3-thiazinan-4-ones

Abstract

Racemic 2-(2,4-dinitrophenyl)hydrazono)-5,6-diphenyl-1,3-thiazinan-4ones and (Z)-N'-(2,4-dinitrophenyl)-2,3-diphenylacrylohydrazide were formed during the diastereoselective reaction between 4-substituted 1-(2,4-dinitrophenyl)thiosemicarbazides and 2,3-diphenylcycloprop-2enone under refluxing ethanol. The structures of the synthesized compounds were confirmed by single crystal X-ray analyses.

Novel quinoline/thiazinan-4-one hybrids; design, synthesis, and molecular docking studies as potential anti-bacterial candidates against MRSA

“…Treating aniline derivatives 1a–h with polyphosphoric acid (PPA), and diethyl malonate (DEM) at 220 °C afforded 2-quinolones 2a–h . 38 Gentle heating of 2a–h with CHCl 3 and 15% NaOH gave the corresponding 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbaldehydes 3a–h . Reaction of 3a–h with thiosemicarbazide ( 4 ) gave the corresponding thiosemicarbazones 5a–h (Scheme 1), and their structures were confirmed by comparing their spectral data to those previously published.…”

Synthesis and structure confirmation of 2,4-disubstituted thiazole and 2,3,4-trisubstituted thiazole as thiazolium bromide salts

“…Mono and di-substituted thiosemicarbazides were prepared according to literature methods (1a [24], 1b [25], 1c [26], 1d [27], 7a-7e [28]). Phenacyl bromides 2a, 2b were prepared according to literature [29,30].…”

Heterocycles from cyclopropenones

“…However, the carbonyl group of 1 was attacked by N4-H, resulting in the formation of the product 128 via intermediate D (Scheme 81). 119 When pyrazolylthioureas 130a-c were subjected to 1b, the reaction proceeded to give compounds 131a-c in 75-90% yield (Scheme 82). The reaction was performed in ethanol for 4-7 h in the presence of DDQ as the oxidizing agent.…”

“…), DCE, rt, 6 h. reaction afforded compounds 128a-e, as well as a side product 129. 119 The reaction mechanism could be simply described as the conjugate double bond of 1b was attacked by the sulfur atom generating intermediate A. The intermediate B was formed via the intramolecular nucleophilic attack of N4-H on C]O, which rearranged to generate 128.…”

“…However, the carbonyl group of 1 was attacked by N4–H, resulting in the formation of the product 128 via intermediate D (Scheme 81). 119…”