Effective pathways for an enantiospecific synthesis of (1aS, 8bS)-1-tert-butyloxycarbonyl-8-formyl-1, 1a, 2, 8b-tetrahydroazirino[2', 3' : 3, 4]pyrrolo[1, 2-α]indole (8) were investigated as a preliminary experiment aiming at chiral syntheses of aziridinomitosenes 5 and (1aS, 8bS)-8-[[(aminocarbonyl)oxy]methyl]-5-formyl-7-hydroxy-1, 1a, 2, 8b-tetra-hydroazirino[2', 3' : 3, 4]pyrrolo[1, 2-α]indone (6a). An aldehyde 14, derived from L-serine was condensed with 2-lithio-1-(phenylsulfonyl)indole (10) to afford diastereomers 15a and 15b, whose stereochemistry was unambiguously determined by ¹H-NMR studies of the 1, 3-dioxane derivatives 17a, 17b, and 18 as well as the X-ray crystallographic analysis of a dihydropyrrolo[1, 2-α]indole derivative 31a. The latter compound was prepared from 15a via the following operations(Chart 5) : (i) removal of the acetonide and the indole-protecting groups, followed by acetylation to form 29a, (ii) Vilsmeier reaction to produce 30a, and (iii) hydrolysis of acetyl groups, partial methanesulfonylation (mesylation), and treatment with potassium carbonate in acetonitrile. A diastereomer 31b was obtained from 15b in a similar manner.Both isomers 31a and 31b afforded the desired compound 8 upon treatment with a mesylation reagest followed by potassium tert-butoxide in tetrahydrofuran.