摘要:
The present invention provides a new and efficient process for the preparation of the dexmethylphenidate hydrochloride with high optical purity, the process comprising: (a) reacting a solution of threo-N-Boc-ritalinic acid with (S)-1-phenylethylamine, separating precipitated solid salt of (R,R)-enriched N-Boc-ritalinic acid with (S)-1-phenylethylamnine from the reaction mixture and recrystallizing, reslurring and/or trituring of said salt; (b) mixing the solid salt of (R,R)-N-Boc-ritalinic acid and (S)-1-phenylethylamine obtained in step (a) with aqueous acid and separating (R,R)-N-Boc-ritalinic acid from the mixture; and (c) reacting the (R,R)-N-Boc-ritalinic acid prepared in step (b) with hydrogen chloride and methanol to give dexmethylphenidate hydrochloride with optical purity of at least 99% ee. The present invention further provides salt of (R,R)-N-Boc-ritalinic acid with (S)-1-phenylethylamine as new intermediate in the preparation of dexmethylphenidate hydrochloride.
摘要:
Methods for making trans-(−)-Δ9-tetrahydrocannabinol and trans-(+)-Δ9-tetrahydrocannabinol are disclosed herein. In one embodiment, a trans-(−)-Δ9-tetrahydrocannabinol composition is prepared by allowing a composition comprising (±)-Δ9-tetrahydrocannabinol to separate on a chiral stationary phase to provide a trans-(−)-Δ9-tetrahydrocannabinol composition comprising at least about 99% by weight of trans-(−)-Δ9-tetrahydrocannabinol based on the total amount of trans-(−)-Δ9-tetrahydrocannabinol and trans-(+)-Δ9-tetrahydrocannabinol. The invention also relates to methods for treating or preventing a condition such as pain comprising administering to a patient in need thereof an effective amount of a trans-(−)-Δ9-tetrahydrocannabinol having a purity of at least about 98% based on the total weight of cannabinoids.
摘要:
Methods for making trans-(−)-Δ9-tetrahydrocannabinol and trans-(+)-Δ9-tetrahydrocannabinol are disclosed herein. In one embodiment, a trans-(−)-Δ9-tetrahydrocannabinol composition is prepared by allowing a composition comprising (±)-Δ9-tetrahydrocannabinol to separate on a chiral stationary phase to provide a trans-(−)-Δ9-tetrahydrocannabinol composition comprising at least about 99% by weight of trans-(−)-Δ9-tetrahydrocannabinol based on the total amount of trans-(−)-Δ9-tetrahydrocannabinol and trans-(+)-Δ9-tetrahydrocannabinol. The invention also relates to methods for treating or preventing a condition such as pain comprising administering to a patient in need thereof an effective amount of a trans-(−)-Δ9-tetrahydrocannabinol having a purity of at least about 98% based on the total weight of cannabinoids.