Derivatives of α,β-dehydroamino acids: V. Intramolecular cyclization of 2-{2-[(Z)-1-Benzamido-2-phenylvinyl]acetamidomethyl}benzimidazole

Polymer-Supported Stereoselective Synthesis of Benzimidazolinopiperazinones

“…1,2 On the other hand, Roughley, 1 and coworkers documented that between one-quarter and one-half of carbon atoms are sp 3 -hybridized, although it seems that most of the recently prepared compounds by medicinal chemists are "flat". To contribute to syntheses of chiral compounds with higher degrees of unsaturation, we developed efficient synthesis of 4,7,8,10-tetrasubstituted-(((4S,10aS)-3-oxo-3,4,10,10atetrahydrobenzo [4,5]imidazo[1,2-a]pyrazin-2(1H)-yl)alkyl)amides.…”

“…10 The latter synthetic approach involved a four-component Ugi−Smiles reaction, which was followed by an acid-catalyzed cyclization, an intramolecular reductive cyclization, and an oxidation. 10 Other related derivatives, such as deazaanalogues of compound II, 1,2-dihydrobenzo [4,5]imidazo[1,2-a]pyridin-3(5H)-ones III (Figure 1), are reportedly anxiolytic, 11−13 antiviral, 14 and antimicrobial 15 agents. 3,4,4a,5-Tetrahydrobenzo [4,5]imidazo [1,2-a]pyridin-1(2H)-ones linked by benzimidazoles have also been documented.…”

“…10 Other related derivatives, such as deazaanalogues of compound II, 1,2-dihydrobenzo [4,5]imidazo[1,2-a]pyridin-3(5H)-ones III (Figure 1), are reportedly anxiolytic, 11−13 antiviral, 14 and antimicrobial 15 agents. 3,4,4a,5-Tetrahydrobenzo [4,5]imidazo [1,2-a]pyridin-1(2H)-ones linked by benzimidazoles have also been documented. 16 The aromatic part of 1,2-dihydrobenzo [4,5]imidazo [1,2-a]pyrazin-3(4H)-ones II, benzimidazoles, were synthesized several times, in solution 17−21 and on solid phase.…”

“…3,4,4a,5-Tetrahydrobenzo [4,5]imidazo [1,2-a]pyridin-1(2H)-ones linked by benzimidazoles have also been documented. 16 The aromatic part of 1,2-dihydrobenzo [4,5]imidazo [1,2-a]pyrazin-3(4H)-ones II, benzimidazoles, were synthesized several times, in solution 17−21 and on solid phase. 22−25 Benzimidazole derivatives can serve as angiotensin II receptor antagonists, 26 as inhibitors of trypsinlike serine protease (factor Xa), 27 and as antibacterial agents.…”

“…28 The synthesis of benzimidazolines and their closely related compounds, 2-oxo/thioderivatives and spiro-benzimidazolines, has also been described. 16,29−34 On the other hand, 1,2,10,10a-tetrahydrobenzo [4,5]imidazo-[1,2-a]pyrazin-3(4H)-ones I can be considered not only as benzimidazolines fused with piperazin-2-one cycle but also as hexahydroimidazo[1,2-a]pyrazin-6(5H)-ones IV (Figure 1) fused with benzene ring. The synthesis of hexahydroimidazo-[1,2-a]pyrazin-6(5H)-ones IV and their closely related compounds has been reported many times, in solution 35−38 and on solid phase.…”