Chapter I describes the stereocontrolled total synthesis of (−)-safracin B with antibacterial and antitumor activities. The convergent approach for the synthesis of safracin B can be readily applied to the synthesis of the related isoquinolinequinone family such as saframycins and ecteinascidins. Chapter II discusses the total synthesis of (−)-thiangazole, a substance with potent anti-HIV-1 activity in vitro. An efficient synthetic pathway is developed to enable diverse modification of both ends of thiangazole and thus provide a rapid access to a variety of analogs. Chapter III outlines the development of new chemistry of nitrobenzenesulfonamides, N-Boc and N-Alloc nitrobenzene sulfonamides, and alkylsulfonamides for the efficient preparation of secondary amines and protected primary amines.