Diterpenoids from the flowers of Rhododendron molle.
A new seco-kalmane-type diterpenoid, seco-rhodomollone (1), five new grayanane-type diterpenoids, rhodomollein XXI (2), 6-O-acetylrhodomollein XXI (3), 6,14-di-O-acetylrhodomollein XXI (4), rhodomollein XXII (5), and 2-O-methylrhodomollein XI (6), and two new kalmane-type diterpenoids, rhodomolleins XXIII (7) and XXIV (8), together with seven known compounds, were isolated from the flowers of Rhododendron molle collected in Guangxi Province, China. The absolute configurations of 1 and 3 were defined by single-crystal X-ray diffraction experiments. Compound 1 possesses an unprecedented 1,5-seco-kalmane skeleton presumably derived by cleavage of the C-1-C-5 bond of the kalmane skeleton. Compounds 2-4 represent the first examples from a natural source of grayanane-type diterpenoids with a chlorine substituent.
State Key Laboratory of Drug Research & Natural Products Chemistry Department, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , 555 Zu-Chong-Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, People's Republic of China.
Shuai-Zhen
SZ
Zhou
Sheng
S
Yao
Chunping
C
Tang
Changqiang
C
Ke
Lu
L
Li
Ge
G
Lin
Yang
Y
Ye
D018360:Crystallography, X-Ray; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification*; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification*; D035264:Flowers / Q000737:chemistry; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D029793:Rhododendron / Q000737:chemistry*
D004224:Diterpenes; D004365:Drugs, Chinese Herbal; C069462:rhodomollein III