Bioactive aporphine alkaloids from Fissistigma tungfangense.

Three new aporphine alkaloids, fissitungfines C–E ( 1–3 ), together with five known analogues ( 4 – 8 ) were isolated from the stems of Fissistigma tungfangense . Their structures were elucidated by extensive spectroscopic methods Among them, fissitungfines C ( 1 ) and D ( 2 ) are two unusual aporphine alkaloids with a carboxyl group as a substituent at N-6. All isolated compounds were evaluated for their anti-rheumatoid arthritis activities via examining their anti-proliferative effects on synoviocytes in vitro . Fissitungfine E ( 3 ) exhibited a significant inhibitory effect on the proliferation of synoviocytes comparable to that of methotrexate. [ABSTRACT FROM AUTHOR]