Synthetic studies on erythromycin derivatives: reactivity of the C12-21 alkene.
The reactivity of the C12-21 alkene of some erythromycin A derivatives was studied. This double bond was easily oxidized to the corresponding epoxide with excellent stereoselectivity. A single crystal X-ray structure showed that the epoxide moiety was on the same side as the acetonide. When an erythromycin derivative containing a C12-21 alkene was treated with diazomethane a [3+2] cycloaddition affording a pyrazoline occurred. In the case of 6-O-allylated erythromycin derivatives the C12-21 alkene was selectively epoxidized in the presence of the 6-O-allyl moiety. These results show that the C12-21 alkene is an active reaction site, which can be used for useful further modification of erythromycin derivatives.
Chen
Wei-Min
WM
Department of Medicinal Chemistry, School of Pharmacy, Jinan University, Guangzhou, 510632, P.R.China. twmchen@jnu.edu.cn
D000475:Alkenes / Q000138:chemical synthesis* / Q000378:metabolism*; D002384:Catalysis; D003500:Cyclization; D004852:Epoxy Compounds / Q000737:chemistry / Q000378:metabolism; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000737:chemistry*; D008954:Models, Biological; D011720:Pyrazoles / Q000737:chemistry / Q000378:metabolism
D000475:Alkenes; D004852:Epoxy Compounds; D011720:Pyrazoles; D004917:Erythromycin