Synthesis and biological activity of DL-3-(5-benzimidazolyl)-2-methylalanine

Synthesis and preliminary biological studies of 4- and 5-[2-hydroxy-3-(isopropylamino)propoxy]benzimidazoles: selective β2 adrenergic blocking agents

“…Compound 3 was also prepared by a seldom used method for the synthesis of ß blockers. 16,17 As seen in Scheme II, l-benzyl-5-hydroxybenzimidazole (10) can be reacted with l-isopropyl-3-azetidinol (11) to attach the side chain in a single step. However, the entire route is only one step shorter than the previous scheme and suffers certain drawbacks: the azetidinol is not easily synthesized, and, in addition, intermediate 12 is difficult to purify.…”