Work

Cytotoxic and Noncytotoxic Steroidal Constituents of Cryptolepis dubia

Year: 2025

Type: article

Abstract: (−)-Cryptanoside A ( 1 ) was identified previously as a major cytotoxic component of the stems of Cryptolepis dubia collected in Laos, which mediates its activity by targeting Na + /K + -ATPase (NKA), with hydrogen bonds formed between its 11- and 4′-hydroxy groups and NKA being observed in its docking profile. In a continuing investigation, 1 and its 17-epimer, (−)-17- epi -cryptanoside A ( 2 ), and the new (+)-2-hydroxyandrosta-4,6-diene-3-one-17-carboxylic acid ( 3 ) and the known (+)-2,21-dihydroxypregna-4,6-diene-3,20-dione or 2-hydroxy-6,7-didehydrocortexone ( 4 ) pregnane-type steroids were isolated from C. dubia . In addition, (−)-11,4′-di- O -acetylcryptanoside A ( 1a ) has been synthesized from the acetylation of 1 . The structures of these compounds were determined by analysis of their spectroscopic data, with their cytotoxic and NKA inhibitory activities being evaluated. In contrast to 1 that exhibited potent activities, the other compounds were largely inactive. Molecular docking profiles indicated that 1 – 3 and 1a bind to NKA, but some subtle differences were observed in their interactions with NKA, which may contribute to their differential cytotoxic and NKA inhibitory potency.

Source: Journal of Natural Products

DOI: 10.1021/acs.jnatprod.4c01257