One-Step Assembly of Carbamoyl-Substituted Heteroannelated [1,4]Thiazepines

Abstract

We present a convenient synthesis of novel heteroaryl-fused 3-oxo-1,4-thiazepine-5-carboxamides and 5-oxo-1,4-thiazepine-3-carboxamides using a modification of four-component Ugi condensation. We demonstrate the usefulness and versatility of the developed approach for the synthesis of variously substituted compounds and discuss the scope and limitations of the chemistry involved.

Expedient Entry into 1,4-Dihydroquinoxalines and Quinoxalines via a Novel Variant of Isocyanide-Based MCR

“…Notable examples include: i) Groebke reaction of 2-aminoazines and azoles, 3,4 ii) ring-forming Ugi-type reactions of various aldehydo and keto acids, 5,6 iii) aqueous-phase b-lactam synthesis from b-amino acids, 7 and many others.…”

Synthesis of Indolobenzazepinones by Application of an Isocyanide‐Based Multicomponent Reaction

“…Compounds 4a – c were engaged in intramolecular Ugi4‐CRs – based on the optimized conditions developed by Ivachtchenko et al for the synthesis of thiazepines starting from oxo acids7b – with a variety of isocyanides and primary amines (Figure 2). We were pleased to observe that the reactions occur smoothly without any protecting group on the indole moiety.…”

5-Chloropyrazole-4-carboxaldehydes as synthon in heterocyclic synthesis

“…Anderson et al [69] reported that one-pot condensation of 4 with Na 2 S 9 H 2 O and propan-2-amine (156) or 2,5-dimethylhexane-2,5-diamine (157) On the other hand, Ilyn et al [73] Reported that reaction of 4 with disodium thioacetate 176 in methanol afforded the corresponding acid 177, which condensed with various amines 178 and isocyanides 179 in methanol to form heteroaryl-fused derivatives of 3-oxo-1,4-thiazepine-5-carboxamides 180 (Scheme 40). 5-Allylsulfanyl-3-methyl-1-phenylpyrazole-4-carbaldehyde (182) was achieved via a one-pot reaction of allyl bromide 181, thiourea and 4 in ethanol in the presence of NaOH [70].…”