Manufacturing Process
Manufacturing process for BEPOTASTINE BESILATE includes these steps as follows: Step A: Synthesis of Methyl 2-endo-hydroxy-1-exo-hydroxymethyl-3a,8b-cis-2,3,3a,8b-tetrahydro-
1H-5-cyclopenta[b]benzofurancarboxylate,Step B: Synthesis of Methyl 3-methyl-trans-4a-cisoid-4a,5a-cis-5a-1,4a,5,5a,10b,10c-hexahydro-7-
dioxin o[5,4-a]cyclopenta[b]benzofurancarboxylate,Step C: Synthesis of 3-Methyl-trans-4a-cosoid-4a,5a-cis-5a-1,4a,5,5a,10b,10c-hexahydro-7-
dioxino[5,4-a]cyclopenta[b]benzofuranylmethanol,Step D: Synthesis of 7-Chloromethyl-3-methyl-trans-4a-cisoid-4a,5a-cis-5a-1,4a,5,5a,10b,10chexahydrodioxino[5,4-a]cyclopenta[b]benzofuran,Step E: Synthesis of 4-[3-Methyl-trans-4a-cisoid-4a,5a-cis-5a-1,4a,5,5a,10b,10c-hexahydro-7-
dioxino[5,4-a]cyclopenta[b]benzofuranyl]butyric acid, Step F: Synthesis of Methyl 4-[2-endo-hydroxy-1-exo-hydroxymethyl-3a,8b-cis-2,3,3a,8btetrahydro-1H-5- cyclopenta[b]benzofuranyl]butyrate, Step G: Synthesis of Methyl 4-[2-endo-acetoxy-1-exo-hydroxymethyl-3a,8b-cis-2,3,3a,8btetrahydro-1H-5-cyclopenta[b]benzofuranyl]butyrate, Step H: Synthesis of Methyl ester of 11,15-dideoxy-11-acetoxy-16-methyl-15-oxo-18,19-
tetradehydro-5,6,7-trinor-4,8-inter-m-phenylene PGI2,Step I: Synthesis of 11-Deoxy-11-acetoxy-16-methyl-18,19-tetradehydro-5,6,7-trinor-4,8-inter-mphenylene PGI2.To a solution of 54 mg of methyl ester of 11-deoxy-11-acetoxy-16-methyl-
18,19-tetradehydro-5,6,7-trinor-4,8-inter-m-phenylene PGI2 in 4.5 ml of
anhydrous methanol was added 0.001 ml of 4.8 N sodium methoxide under
argon, and the reaction mixture was stirred for 1.5 hours at room
temperature.
After addition of acetic acid to the reaction mixture and concentration of the
mixture, the residue was dissolved in 20 ml of ethyl acetate, and the solution
was washed with aqueous saturated solution of sodium hydrogen carbonate,
water and aqueous saturated solution of sodium chloride, dried and
concentrated to afford 55 mg of an oily material.
This oily material was purified by column chromatography using ethyl acetate
and cyclohexane (3:1) as eluent to give 48 mg of the methyl ester of 16-
methyl-18,19-tetradehydro-5,6,7-trinor-4,8-inter-m-phenylene PGI2.