Direct Amination and Synthesis of Fused N‐Substituted Isothiochromene Derivatives

Abstract

Isothiochromene[3,4‐d] pyrimidine derivatives 2, 3, and 4a,b were synthesized from the reaction of 3‐amino‐1‐(pyridin‐4‐yl)‐5‐(pyridin‐4‐ylmethylene)‐5,6,7,8‐tetrahydro‐1H‐isothiochromene‐4‐carbonitrile 1 with acetic anhydride, formamide, urea, or thiourea in appropriate experimental conditions. Combination of 1 with carbon acid derivatives afforded isothiochromene [3,4‐b]pyridine 6–8 in good yield. A simple approach for N‐substituted fused isothiochromene derivatives has been explored. A POCl3‐mediated direct amination of isothiochromene amide 2 with NH2‐heterocycles, secondary amines, and carbohydrazides is described and compared with classical method, yielding 10–14. The structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, and spectral data.

Synthesis of 1,2,4‐triazolopyridazines, isoxazolofuropyridazines, and tetrazolopyridazines as antimicrobial agents

“…Recently, it is well known in pyridazinones chemistry that position number of three in the pyridazinone ring and fused pyridazinone displayed distinct activities toward nucleophiles. Therefore, 3-chloro-6-phenyl-4-(pyridin-4ylmethylene)-4,5-dihydropyridazine (11) was synthesized from the reaction of (4) with phosphorus oxychloride (POCl 3 ) [36] or phosphorus pentachloride (PCl 5 ) and then heat and reflux on a steam bath for 8 to 12 hours. The IR spectrum of 11 exposed the absence of NH and carbonyl groups, and the 1 H-NMR spectrum of 11 showed the absence of NH group, while the two singlet signals at 2.90 and 8.10 for corresponding to the two protons of (CH 2 ) and one proton of (CH) methine.…”

“…Our research group has published a lot of scientific research that include many biological and pharmaceutical activities. [18,[30][31][32][33][34][35][36][37][38] Furthermore, with the continuation of the research work in this manuscript, we have prepared many of heterocyclic compounds such as furopyridazinones, isoxazolopyridazines, tetrazolopyridazines, pyridazinoquinazolinones, piperazinyl and morpholinopyridazines, hydrazinylpyridazines, and 1,2,4-triazolopyridazines with studying their activities as antimicrobials in vitro.…”

Synthesis of new pyrazoles, oxadiazoles, triazoles, pyrrolotriazines, and pyrrolotriazepines as potential cytotoxic agents

“…In continuation of our past work in the synthesis of heterocyclic compounds that have different biological and pharmaceutical activities. [ 2–11,28,32–33,40–45 ] So, in this manuscript, we prepared new heterocyclic compounds via new procedures such as pyrazoles, 1,3,4‐oxadiazoles, 1,2,4‐triazoles, 1,2,4‐triazines, pyrrolotriazines, 1,2,4‐triazepinones and pyrrolotriazepinones and these new compounds are very important class because they afford a wide range of pharmacological activities as, antitumor activity through present study in the manuscript.…”

Recent progress on the chemistry of thieno[3,2‐b]quinoline derivatives (part III)

“…Our research group, in recent years, has published many scientific types of research studies [ 55–73 ] in the field of chemistry for heterocyclic compounds that have wide biological activity. Therefore, we created this review article to present it to all researchers in this field for thieno[3,2‐ b ]quinolines derivatives, In this review, we have discussed the method of synthesized and the chemical reactions of thieno[3,2‐ b ]quinolones, starting from cinnamic acid, 2‐Bromo‐5‐methoxybenzoic acid, 2‐([1H‐pyrrol‐3‐yl]thio) acetic acid, 4‐phenylbutan‐2‐one, thiophenol, thiophene, aryldithioate, and 2‐phenylquinoline.…”