A kind of iodine medium preparation method of chiral pyrazole spirofuran compound

Abstract

The invention provides an iodine-mediated preparation method of chiral pyrazole spirofuran compounds shown in formula (I), the synthesis method is carried out as follows: the o-hydroxyl nitroalkene shown in formula (II) Compounds and pyrazolone compounds shown in formula (III), chiral squaraine catalysts, and organic solvents are mixed, and reacted at -60 to 60°C for 1 to 48 hours to obtain compounds shown in formula (IV). Add an iodine source additive and an alkali to the compound shown in (IV), react at -60 to 60°C for 1 to 48 hours, and the reaction solution is post-treated to obtain the chiral pyrazole spirofuran compound shown in the formula (I); the present invention The reaction conditions are mild, the product yield is high, and the selectivity is excellent.

Description

[0001] (1) Technical field

[0002] The invention relates to an iodine-mediated preparation method of chiral pyrazole spirofuran compounds.

[0003] (2) Background technology

[0004] Chiral pyrazole spirocyclic compounds exist in a large number of biologically active natural products and clinical medicines, which have a wide range of biological activities, such as antipyretic, neuroprotective, anti-analgesic, anti-bacterial, anti-fungal, anti-inflammatory, anti-tumor effects. The common structures of chiral pyrazole spirocyclic compounds include pyrazole spirocyclopentane, pyrazole spirocyclohexane, pyrazole spirocyclohexanone, pyrazole spirocyclohexenone, etc., such as: the scientific name is 4-(3 ,4-dimethoxyphenyl)-2-(1-(5-hydroxy-2-methylbenzoyl)-4-piperidinyl)-2,3-diazaspiro[4.4]nonane - Compound A of 3-en-1-one and scientific name N-(3-isobutyl-4-oxa-2,3-diazaspiro[4.5]dec-1-en-8-yl Compound B of )-4-(1H-pyrazol-1-yl)benzenesulfonamide is a phosphodiesterase PDE4 inhi...

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