Abstract: Disclosed is a novel tenofovir disoproxil edisylate salt having the structure of Chemical Formula 1.

Abstract: This invention relates to a novel doripenem crystal, a solvate thereof, and a preparation method thereof and, more specifically, to a novel doripenem anhydride crystal, a method of preparing the doripenem anhydride crystal using various solvents, and a solvate of doripenem.

Abstract: Disclosed is a novel tenofovir disoproxil edisylate salt having the structure of Chemical Formula 1.

Abstract: This invention relates to a novel doripenem crystal, a solvate thereof, and a preparation method thereof and, more specifically, to a novel doripenem anhydride crystal, a method of preparing the doripenem anhydride crystal using various solvents, and a solvate of doripenem.

Abstract: There is disclosed an azetidinone compound of the formula (I): wherein R is hydrogen, or a hydroxy protecting group, R1 and R2 are each independently alkyl of 1-15 carbon atoms, benzyl or cyclized together with the carbon atom to which they are attached to form a 5 or 6-membered cyclic hydrocarbon or a heterocyclic radical having one or two hetero ring atoms, said hetero ring atoms being selected from the group consisting of O and S; R3 is lower alkyl or —COO(lower alkyl) R4 is phenyl, or phenyl substituted with halogen, lower alkoxy or nitro which is useful as a synthetic intermediate to the 1??-methylcarbapenem-type antibacterial agent.

Abstract: There is disclosed an azetidinones compound of the formula (I): Wherein, R is hydrogen, or hydroxy protecting group, R1 and R2 are each independently alkyl of 1-15 carbon atoms, benzyl or cycloalkyl of 5-6 carbon atom which may have substituent(s), R3 is low alkyl, or low alkyl ester, R4 is aryl, or aryl substituted with halogen, alkoxy of 1-6 carbon atom, nitro groups which is useful as a synthetic intermediate of the 1′&bgr;-methylcarbapenem-type antibacterial agent.