Abstract:
The present invention provides desosamine and mycaminose analogs and nitro sugars and methods for their preparation. The invention also provides methods of cyclizing a compound of Formula (A′) with glyoxal to give a nitro sugar of Formula (B). Methods for the preparation of compound of Formula (D′) are provided comprising cyclization of a nitro alcohol to give a nitro sugar and reduction and alkylation of the nitro sugar to give a desosamine, mycaminose, or an analog thereof.
Abstract:
The present invention provides desosamine and mycaminose analogs and nitro sugars and methods for their preparation. The invention also provides methods of cyclizing a compound of Formula (A′) with glyoxal to give a nitro sugar of Formula (B). Methods for the preparation of compound of Formula (D′) are provided comprising cyclization of a nitro alcohol to give a nitro sugar and reduction and alkylation of the nitro sugar to give a desosamine, mycaminose, or an analog thereof.
Abstract:
The present invention provides a halogenated aniline represented by formula (I) (wherein each of X1 and X2 independently represents a chlorine atom, a bromine atom or an iodine atom), a method for producing the halogenated aniline, and other aspects.
Abstract:
The present invention relates to an n-heterocyclic carbene (NHC) type palladium catalyst and its preparation method as well as applications. Its preparation process is as below: select glyoxal as the raw material to synthesize glyoxaldiimine in the presence of Lewis acid or Bronsted acid, and then react with paraformaldehyde to get the NHC type ligand. Use palladium(II) to react with the compound containing carbon-nitrogen double bonds to get palladium(II) cyclic dimer; make the palladium cyclic dimer and the NHC type ligand coordinated to get the NHC type palladium catalyst. The palladium catalyst with a brand new structure according to the present invention, boasts high activity and multi-purpose. In addition, it shows excellent reaction activity in a lot of catalytic-coupling reactions including Suzuki-Miyaura, Heck, Buchwald-Hartwig, Kumada-Tamao-Corriu, Sonogashira, Negishi and α-ketone arylation reactions, and some reactions even can be carried out with the presence of an extremely low concentration of catalyst, exhibiting favorable industrialization prospect.
Abstract:
Disclosed is a process for preparing dihydro-2H-pyran derivatives of formula I: wherein R1 and R2 are defined herein. The process of the invention provides the compound of formula I in concise cascade reactions and in one pot. The compound of formulae I prepared by the process of the invention and its further transformed derivatives are useful for making pharmaceutical composition for the treatment of proliferative diseases.
Abstract:
The present invention describes immobilized haloenamine reagents, immobilized tertiary amides, methods for their preparation, and methods of use.
Abstract:
A process for the preparation of chlorofluoronitrobenzenes and difluoronitrobenzenes, which comprises heating dichloronitrobenzene to not more than 200.degree. C. in excess with an alkali metal fluoride having a total water content of about 0.2 to about 2.5% by weight in the presence of a quaternary ammonium and/or phosphonium salt, crown ether and/or polyethylene glycol dimethyl ether as catalyst in the absence of a solvent.
Abstract:
2-Nitro-3,6-dichlorophenol is prepared by sulfonation of 2,5-dichlorophenol and subsequent nitration and desulfonation, in which the nitration is carried out by metering in a nitrating acid composed of 98 to 100% strength nitric acid and 96 to 100% strength sulfuric acid at temperatures from -15.degree. to 35.degree. C. and a metering time of at least 1 hour.
Abstract:
Nitromethane is preparaed from a nitriding agent comprising an oxygenated nitrogen compound and a carbon compound containing two carbon atoms and at least one atom other than carbon and hydrogen.