13. COOH COOH OCOCH, 14, CH 0 ·HBr3H2O 15. CH,OH 00C H C.Hs HOCH2 16. HO CHCH,NHC(CH;), OH HN 17. H:N C-CH,CH2-N ·HCl OH 19 HO- CH2 CH,NH2·HCl 20. H 51913. <>-吼叫芦义:: COOH 1 OCOCH3 /飞 、、/' HOCHz 16. HO OH 17. 18. 19. CI 什只 • Hel 519