Abstract: The present invention relates to the field of medicine, and disclosed are an L-setastine hydrochloride and a preparation method therefor. The compound of the present invention has the advantages of stronger histamine Hi receptor antagonism and small side effect; the yield of the preparation method is more than 80%, and the product purity is high. The present invention also provides an application of the compound as an H1 histamine receptor antagonist.

Abstract: A method of preparing (S)-2-amino-5-methoxytetralin hydrochloride[(S)-2-amino-5-methoxyl-1,2,3,4-tetrahydronaphthalene hydrochloride], comprising the steps of: (1) producing a compound (I) by addition-elimination reaction of 5-methoxy-2-tetralone and R-(+)-a-phenylethylamine; (2) producing a compound (II) by reduction reaction of the compound (I) with a reducing agent; and (3) producing a compound (II) hydrochloride by reacting the compound (II) with a salt-forming agent, then carrying out reduction reaction with a palladium-carbon catalyst to produce (S)-2-amino-5-methoxytetralin hydrochloride. The method can significantly increase the yield of (S)-2-amino-5-methoxytetralin hydrochloride with short synthetic path, low preparation cost and less pollution, which is environmentally friendly and is suitable for medical industrialized production. The structural formulae of the compound (I) and the compound (II) are: respectively.

Abstract: The present invention relates to the field of medicine, and disclosed are an L-setastine hydrochloride and a preparation method therefor. The compound of the present invention has the advantages of stronger histamine Hi receptor antagonism and small side effect; the yield of the preparation method is more than 80%, and the product purity is high. The present invention also provides an application of the compound as an H1 histamine receptor antagonist.

Abstract: A method of preparing (S)-2-amino-5-methoxytetralin hydrochloride[(S)-2-amino-5-methoxyl-1,2,3,4-tetrahydronaphthalene hydrochloride], comprising the steps of: (1) producing a compound (I) by addition-elimination reaction of 5-methoxy-2-tetralone and R-(+)-a-phenylethylamine; (2) producing a compound (II) by reduction reaction of the compound (I) with a reducing agent; and (3) producing a compound (II) hydrochloride by reacting the compound (II) with a salt-forming agent, then carrying out reduction reaction with a palladium-carbon catalyst to produce (S)-2-amino-5-methoxytetralin hydrochloride. The method can significantly increase the yield of (S)-2-amino-5-methoxytetralin hydrochloride with short synthetic path, low preparation cost and less pollution, which is environmentally friendly and is suitable for medical industrialized production. The structural formulae of the compound (I) and the compound (II) are: resepectively.