Marsogenin: a new pregnane ester from Marsdenia tenacissima

A new pregnane, 12β-O-acetyl-20(S)-O-N-methylanthranilyl-3β, 8β, 14β, 17α-tetrol pregn-5-ene (12β-O-acetyl-20(S)-O-N-methylanthranilyl-sarcostin) have been isolated from Marsdenia tenacissima (family: Asclepediaceae). The structure of new pregnane was elucidated by using spectroscopic techniques,¹H,¹³C NMR, HMBC, HSQC, COSY and TOCSY and ESI-MS Mass spectrometry.