CH3 CN (10) (11k (12)CH3CH一C-CH CH3 Br (13)(S-CH3 CHCH2OH (14) (15) 16 7.(A),(B),(C)结构式分别为 X Xar>(9) (10) CH3 OEt CN (11) (12) CH3 CH3 CN CH3CH C CH3 CH3 CH3 Br (13) (14) CN (15) (16) Br I (S)-CH3CHCH2OH 7. (A), (B), (C)结构式分别为: Br (A) (B) (C)