Efficient and practical synthesis of L-hamamelose.
An efficient synthetic route of L-hamamelose was successfully accomplished starting from D-ribose. L-Hamamelose was synthesized in 42% overall yield with six reaction steps via a stereoselective Grignard reaction, a stereoselective crossed aldol reaction and a controlled oxidative cleavage of the double bond of a vinyl diol compound. During the oxidative cleavage of the double bond of the vinyl diol compound with osmium tetroxide and NaIO(4), an over-oxidative cleavage of alpha-hydroxyl aldehyde generated from ring opening of the first cleaved product, formyl lactol, did not occur, probably due to the stability of the lactol form. A plausible mechanism for the stereoselective crossed aldol reaction was suggested. The final target compound, L-hamamelose can play a very important role as a chiral building block in synthesizing a wide variety of enantiopure compounds.
Kim
Won Hee
WH
Laboratory of Medicinal Chemistry, College of Pharmacy and Research Institute for Drug Development, Pusan National University, Busan 609-735, Republic of Korea.
Kang
Jin-Ah
JA
Lee
Hyung-Rock
HR
Park
Ah-Young
AY
Chun
Pusoon
P
Lee
Boeun
B
Kim
Jungsu
J
Kim
Jin-Ah
JA
Jeong
Lak Shin
LS
Moon
Hyung Ryong
HR
D006601:Hexoses / Q000138:chemical synthesis*; D019906:Nuclear Magnetic Resonance, Biomolecular; D012266:Ribose / Q000737:chemistry; D013237:Stereoisomerism
D006601:Hexoses; C009758:hamamelose; D012266:Ribose