| Abstract: | Based on the spirotryprostatin A structure, a series of compounds belonging to spiro‐indolyl diketopiperazine structural class were designed and synthesized, which embody an oxindole with an all‐carbon quaternary stereocenter. The total synthesis can efficiently be accessed in a seven‐step reaction sequence with 18–28% overall yield from commercially available materials, and a highly enantioselective 1,3‐dipolar cycloaddition, N ‐acylation of the resulting stereochemically complex spiropyrrolidin‐3,3′‐oxindole]s core with Fmoc‐L ‐pro‐Cl and spontaneous ring closure upon N ‐deprotection were obtained. The synthesized compounds 13a–e and 15a–e were evaluated for their antibacterial activities. The result showed that compounds 13b and 15b were active only against Gram‐positive bacteria, and selective antibacterial activity was exhibited by compounds 13d and 13e against Streptococcus lactis . Further, all the remaining compounds showed a certain degree of antibacterial activity. In addition, the structure–activity relationship is also discussed. |
