Process for preparing tetraalkylammonium salt of 6-halogenopurine derivative
申请人:SUMIKA FINE CHEMICALS Co., Ltd.
公开号:EP0967213A1
公开(公告)日:1999-12-29
A process for preparing a tetraalkylammonium salt of a 6-halogenopurine derivative, represented by the formula:
wherein R1 is hydrogen, formyl group or acetyl group; each of R2, R3, R4 and R5 is independently a C1-10 alkyl group; X1 is chlorine, bromine or iodine, comprising reacting a 6-halogenopurine derivative represented by the formula:
wherein R1 and X1 are the same as defined above, or a salt thereof with a tetraalkylammonium salt represented by the formula:
wherein R2, R3, R4 and R5 are the same as defined above; X2 is chlorine, bromine, iodine, an inorganic acid residue or an organic acid residue; n is an integer of 1 to 3. The tetraalkylammonium salt of a 6-halogenopurine derivative is useful as intermediates for preparation of antiviral agents.
Double cone-like crystal form of 2-amino-6-chloropurine and preparation
申请人:Sumika Fine Chemicals Co., Ltd.
公开号:US05789590A1
公开(公告)日:1998-08-04
The present invention is directed to a method for preparing 2-amino-6-chloropurine having a double cone-like crystal form, comprising the steps of: (A) suspending 2-amino-6-chloropurine having an acicular or irregular-shaped crystal form in a liquid consisting essentially of water having a pH of from 3 to 10; and (B) heating the resulting suspension at a temperature of from 70.degree. to 100.degree. C. to complete the double cone-like crystal form conversion.
Method for producing 2-amino-6-halogenopurine and synthesis intermediate therefor
申请人:SUMIKA FINE CHEMICALS Co., Ltd.
公开号:EP0543095A2
公开(公告)日:1993-05-26
The present invention is directed to a method for producing a 2-amino-6-halogenopurine, a novel synthesis intermediate therefor and a method for producing said synthesis intermediate. The desired 2-amino-6-halogenopurine is an intermediate for the production of the compound useful as an antiviral agent, and by using the compound of the present invention as a starting material, the 2-amino-6-halogenopurine can be produced with high yield.