Tinosporoside E and tinosporane A: two new clerodane diterpenes from the tuberous roots of Paratinospora sagittata.

Phytochemical investigation of the tuberous roots of Paratinospora sagittata (Oliv.) Wei Wang led to the isolation of two new clerodane diterpenoids, tinosporoside E and tinosporane A (1 and 2), along with eight known compounds (3-10). The structures of the isolated compounds were determined using spectroscopic and spectrometric techniques. The isolates were screened for antimicrobial activity in vitro. Compounds 5, 9 and 10 showed moderate anti-cryptococcal activity against Cryptococcus neoformans with a minimum inhibitory concentration (MIC) of 64 μg/mL, while compounds 1, 3, 4, 7 and 8 exhibited weaker activity (MIC 128 μg/mL).