CO4370020A1 - PROCESS FOR THE PREPARATION OF ANTIVIRAL AGENTS DERIVED FROM PURINE - Google Patents

Abstract

A PROCESS FOR THE PREPARATION OF A COMPOUND OF FORMULA (A): FIGURE 1 WHERE X IS HYDROGEN, HYDROXY, CHLORINE, C1-6 ALCOXY OR PHENYL C1-6 ALCOXY; AND Ra AND Rb ARE HYDROGEN- OR ACIL OR ITS DERIVATIVES OF PHOSPHATE, WHOSE PROCESS INCLUDES: (i) THE PREPARATION OF A COMPOUND OF FORMULA (I): FIGURE 2 WHERE R1 IS C1-6 ALKYL, OR PHENYL C1 -6 RENT WHERE THE FENIL GROUP IS OPTIONALLY REPLACED; R2 IS HYDROGEN HYDROXY, CHLORINE, C1-6 ALCOXY, PHENYL C1-6 ALKYL SULPHONYL, ACID, AN AMINO GROUP OR A PROTECTED AMINO GROUP, WHOSE PREPARATION INCLUDES THE REACTION OF A COMPOUND OF THE FORMULA (II) 3 WHERE R2 AND R3 ARE AS DEFINED FOR FORMULA (I) WITH: A COMPOUND OF FORMULA (V): FIGURE 4 WHERE L IS AN OUTGOING GROUP AND R1 IS AS DEFINED IN FORMULA (I) TO GIVE A COMPOUND OF FORMULA (VI): FIGURE 5 AND THEREFORE CONVERTS THE INTERMEDIATE COMPOUND OF FORMULA (VI) TO A COMPOUND OF FORMULA (I) THROUGH DECARBOXYLATION, AND AS NECESSARY OR ADVISABLE, BECOMING BECOMING IF THE VARIABLES R1, R2 AND R3 TO OTHER VALUES OF R1, R2 AND R3; (ii) THE CONVERSION OF THE RESULTING COMPOUND FROM FORMULA (I) TO A COMPOUND OF FORMULA (A) THROUGH THE CONVERSION OF VARIABLE R3, TO AMINO, REDUCING THE GROUPS OF ESTERS C02R1 TO CH2OH AND OPTIONALLY FORMING ACIL OR ITS DERIVATIVES OF PHOSPHATE, AND AS NECESSARY OR ADVISABLE, CONVERTING THE VARIABLE R2 IN THE COMPOUND OF FORMULA (I) TO THE VARIABLE X IN THE COMPOUND OF FORMULA (A); CHARACTERIZED IN THE SENSE THAT: R2 IS CHLORINE IN THE FORMULA (I).