The invention discloses a preparation method of
caspofungin. The preparation method comprises steps as follows: pneumocandin B0 and
phenylboronic acid are dissolved in
acetonitrile,
thiophenol is added, the mixture is stirred and uniformly mixed, trifluoromethane
sulfonic acid is added dropwise, and an intermediate MD-I is obtained; the intermediate MD-I and
phenylboronic acid are added to an
anhydrous tetrahydrofuran solution, mixed and dissolved, BSTFA (bis-
trimethylsilyl-trifluoroacetamide) is added under protection of
nitrogen, the mixture continues to have a reaction, a
borane-
tetrahydrofuran solution is added dropwise, the mixture has a reaction,
tetrahydrofuran is removed through reduced pressure
distillation, and an intermediate MD-II is prepared after a product is separated; the intermediate MD-II is dissolved in
methanol, the mixture is cooled under the protection of
nitrogen,
ethylene diamine is added until the mixture reacts sufficiently, and
caspofungin is obtained after freezing
drying. The new preparation method of
caspofungin has the advantages as follows: the
route is short, the reaction condition is mild, post-
processing is simple, the yield is remarkably improved by comparison with that in the prior art, the
total synthesis time can be remarkably shortened, the operative difficulty index and requirements for equipment are reduced to a certain extent, and the production cost is remarkably reduced.