摘要 |
The present invention provides an optically active compound of general formula (I) and salts thereof: wherein R′ is selected from a group consisting of t-butyl amine, n-butylamine, iso-butylamine, iso-propyl amine, 4-phenyl-piperazine-1-ylamine, 4-(2-methoxyphenyl)-piperazin-1-ylamine, and 3,4-dimethoxy phenethyl amine; wherein R1, R2 and R3 are selected from the group consisting of hydrogen, methyl or iso pentenyl; R4, R5 and R6 are selected from the group consisting of Oil, O-alkyl, O-benzyl, O-substituted phenyl or combination thereof.
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