Patents Assigned to NOWA Pharmaceuticals, Co., Ltd.
  • Publication number: 20130137889
    Abstract: Strecker reagents, their derivatives and methods for forming the same and improved Strecker reaction are provided. The electrophiles for asymmetric Strecker reaction include achiral N-phosphorazides, N-phosphoramides, N-phosphonyl imines and their derivatives. The nucleophiles for asymmetric Strecker reaction include chiral BINOL-derived azides, amides, imines and their derivatives, the chiral and achiral diol-based cyanides and their derivatives, the chiral and achiral diamine-based cyanides and their derivatives, the chiral and achiral amino alcohol-based cyanides and their derivatives, the Strecker nucleophiles that are derived from chiral and achiral hydroxyl carboxylic acids and amino acids. Methods of forming the electrophile for asymmetric Strecker reaction comprise the reactions with steps of: a) synthesizing phosphoryl chloride from achiral diamine; b) synthesizing phosphorous azide; c) synthesizing phosphoramide; d) synthesizing the corresponding achiral N-phosphonyl imines.
    Type: Application
    Filed: March 26, 2010
    Publication date: May 30, 2013
    Applicants: NANJING UNIVERSITY, TEXAS TECH UNIVERSITY, NOWA PHARMACEUTICALS CO., LTD.
    Inventors: Guigen Li, Xiangzhen Sun, Huabing Chen
  • Publication number: 20100160681
    Abstract: This application relates to the design and synthesis of new chiral imines reagents which can be utilized for the synthesis of chiral drugs and their precursors. It describes the design of the free NH2-group-attached chiral phosphoramides, a chiral N-phosphonimines and the methods for forming the same. The free NH2-group-attached chiral phosphoramides, having the structure of formula (I): wherein R1 and R2 are independently any organic groups. The synthesis of N-phosphoramides was performed starting from chiral 1,2-diamines via the following steps: N,N?-dialkylation consisting of aldehyde condensation and reduction, cyclization with phosphoryl halide, substitution of halide with azide anion and hydrogenation of azides. The N-phosphonyl imines are synthesized by condensation of N-phosphoramides with aldehydes. Quantitative yield was obtained for each of the four steps without special purification. All precursors were obtained as white solids.
    Type: Application
    Filed: December 16, 2009
    Publication date: June 24, 2010
    Applicant: NOWA Pharmaceuticals, Co., Ltd.
    Inventors: Xiangzhen Sun, Li Guigen