Abstract
Seven new steroidal glycosides, namely pentandrosides A–G, were isolated from the aerial parts of
Tribulus pentandrus. Pentandrosides A–E possess cholestane aglycones, pentandroside F a furostan-type aglycone and pentandroside G an unusual acyloxypregnane aglycone. The structures were elucidated by extensive use of 1D- and 2D NMR experiments along with ESI-MS and HRESI-MS.
Seven new steroidal glycosides named pentandrosides A(
1)–G(
7) were isolated from the EtOH extract of the aerial parts of
Tribulus pentandrus. Pentandrosides A(
1)–E(
5) possess cholestane aglycones, pentandroside F(
6) a furostan-type aglycone and pentandroside G(
7) an unusual acyloxypregnane aglycone probably derived from the degradation of a furostan skeleton. Structure elucidation of
1–
7 was accomplished through the extensive use of 1D- and 2D NMR experiments including
1H–
1H (DQF-COSY, 1D-TOCSY) and
1H–
13C (HSQC, HMBC) spectroscopy along with ESIMS and HRESIMS.