SULFUR-CONTAINING CINNAMIDES WITH ANTIFUNGAL ACTIVITY FROM GLYCOSMIS-CYANOCARPA

Bioassay guided analysis of the methanolic leaf extract of Glycosmis cyanocarpa (Rutaceae) led to the isolation of a new type of sulfur containing cinnamides with antifungal activity: sinharine (cinnamic acid methylsulfidoethylamide) (2) and the corresponding N-methyl derivative methylsinharine (4). In addition, the dominating furoquinoline kokusaginine (3) together with small amounts of skimmianine (5) and the carbazole glycozolidol (1) were also isolated. A series of quinolone and quinazolone alkaloids were detected as minor components by reversed phase HPLC. The structures of 2 and 4 were elucidated by means of spectroscopic methods (IR, UV, H-1 NMR, C-13 NMR, MS). Temperature dependent H-1 NMR and lanthanide induced shifts (LIS) established the stereochemistry of the two conformers of 4.