New Alkaloids from Daphniphyllum longeracemosumRosenth.

✍ Scribed by Lin Li; Hong-Ping He; Ying-Tong Di; Jun-Mian Tian; Xiao-Jiang Hao

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: German
• Weight: 187 KB
• Volume: 89
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200690146

✦ Synopsis

Introduction. -Plants of the genus Daphniphyllum (Daphniphyllaceae) comprise ca. 30 species, of which ten grow in China [1]. They are distinguished for metabolizing a group of highly complex and diversified polycyclic alkaloids that have been challenging subjects in natural-product, synthetic, and biologically oriented chemistry. So far, more than 100 alkaloids have been isolated from the genus Daphniphyllum [2 -10].

Daphniphyllum longeracemosum ROSENTH. is an evergreen tree distributed in Yunnan Province, China. In our search for structurally unique and biogenetically interesting Daphniphyllum constituents, we herein report the isolation and characterization of two new alkaloids from the fruits of D. longeracemosum [11]: daphnilongertone (1) and 11-hydroxydaphnigracine (2). These compounds were obtained together with the known alkaloid dehydrodaphnigracine (3), which had been synthesized before from daphnigracine [12].

Results and

Discussion. -Daphnilongertone (1) was isolated as an optically active, colorless solid. Its molecular formula was determined as C 23 H 33 NO 4 (m/z 388.2499 ([M + H] + ; calc. 388.2487)) by positive-ion HR-ESI-MS, implying eight degrees of unsaturation. The IR spectrum suggested the presence of OH (3441) and C=O (1715, 1725