반응 #531380

반응 방정식

n-butyllithium

maytansinol

n-octyl chloroformate

→

maytansinol 3-n-octylcarbonate

수율 54.5%

용매

THF

반응 조건

후처리

1. 1
   추출Thereafter, at 0° C., the organic layer is extracted with 1.0 ml of saturated sodium chloride and 20 ml of THF
2. 2
   기타The organic layer is dried
3. 3
   workup.DISTILLATIONafter which the solvent is distilled off
4. 4
   기타The residue is purified by silica gel chromatography

실험 절차

In 6.0 ml of dry THF is dissolved 163 mg of maytansinol and under nitrogen gas streams and at -20° C., the solution is treated with 10 molar equivalents of 15% n-butyllithium (n-hexane solution). Then, 556 mg of n-octyl chloroformate is added and the mixture is stirred for 15 minutes. Thereafter, at 0° C., the organic layer is extracted with 1.0 ml of saturated sodium chloride and 20 ml of THF. The organic layer is dried, after which the solvent is distilled off. The residue is purified by silica gel chromatography to obtain 58 mg of maytansinol 3-n-octylcarbonate. Thin layer chromatography on silica gel (Merck HPTLC): Rf=0.61 (developing solvent: chloroform-methanol=95:5),

출처