N O O O HO H 3 C N N O O O HO H 3 C N N O O O HO H 3 C HO HO N CH 3 CH 3 1) CH 3 COOH, H 2 , PtO 2 2) (CH 3 COO) 4 Pb, CH 3 COOH 3) CH 3 COOH, H 2 O CH 2 O (CH 3 ) 2 NH