Chemical Combinatorial Discover High Throughput Screening Physiochemical properties IIn vitro screens InⅤ ivo Screens H/总 File IND Phase i Phase II Phase III File nDa Regist ration MarketL ead identification Discovery High T hroughput Screening P hysiochemical properties Market Regist ration P hase III P hase II P hase I In Vitro screens In Vivo Screens Chemical Combinatorial Clinical L ead optimization F ile IND F ile NDA Pre-clinical Drug interaction studies