合成路线1

7-Aminoquinolin-2-one (III) was prepared by Knorr cyclization of m-phenylenediamine (I) with ethyl acetoacetate (II). Subsequent diazotization of (II), followed by acid hydrolysis gave rise to the 7-hydroxyquinolinone (IV). Alkylation of (IV) with 3-chloro-3-methylbut-1-yne (V), followed by Claisen rearrangement of the resulting propargyl ether (V) afforded the pyranoquinolinone (VII). This was protected as the N-Boc derivative (VIII) by treatment with Boc2O and Et3N. Sharpless asymmetric dihydroxylation of (VIII) using dihydroquinine 2,5-diphenyl-4,6-pyrimidinediyl diether ((DHQ)2-PYR) as the chiral catalyst furnished the (R,R)-diol (IX), which was esterified with (-)-(S)-camphanoyl chloride (X) to produce diester (XI). The Boc protecting group of (XI) was finally removed by treatment with trifluoroacetic acid.