A method for synthesizing pyrazolo[3,4-d]pyrimidin-4-ones

Abstract

The invention provides a novel synthetic method for pyrazolo[3,4-d]pyrimidine-4-ketone compounds. The method employs reaction of hydrazine and methylene malononitrile with aldehyde to synthesize target compounds. The method has a reaction general formula described in the specification, wherein R1 is hydrogen, an alkyl group or an aryl group (wherein the alkyl group and the aryl group can be substituted by one or more selected from the group consisting of halogen, a cyano group, a nitro group, a suIfonyl group, an alkoxyl group, etc.), and the number and the position of the substituted group are not restricted; R2 is hydrogen, or the alkyl group, etc.; R3 is hydrogen, the alkyl group, the alkoxyl group, halogen, a cyano group, a nitro group, or a sulfonyl group, etc.; and R4 is alkane, wherein the alkyl group may be the alkyl group of C1 to C10, preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, or an isobutyl group, etc.; the aryl group may be the aryl group of C6 to C24 and preferably a phenyl group, or a naphthyl group, etc.; and the alkoxyl group may be an alkoxyl group of C1 to C10 and preferably a methoxyl group, or an ethoxyl group, etc. According to the invention, the reaction adopts a conventional heating method, and a purification method is recrystallization. The synthetic method for the pyrazolo[3,4-d]pyrimidine-4-ketone compounds has the following advantages of easily-available raw materials, simple process, mild reaction conditions, convenient after-treatment, high yield, no need of oxidant addition in dehydrogenation process, and convenient industrial production.

Description

(1) Technical field [0001] The invention belongs to the field of organic chemistry, and in particular relates to a pyrazolo[3,4-d]pyrimidin-4-one, specifically a method for preparing pyrazolo[3,4-d]pyrimidin-4-ones compound method. (2) Background technology [0002] Pyrazolo[3,4-d]pyrimidin-4-ones are a class of nitrogen-containing heterocyclic compounds with good biological activity. The research on pyrazolopyrimidinones originated in the 1960s. It was initially found that 6-nitrofuran-substituted pyrazolopyrimidinone compounds have antiviral and antibacterial effects, and it has been reported in the literature that this type of compound has anticancer (Anti-Cancer Drug Des.1999,14,451-459), anticancer Schistosomiasis (J.Med.Chem.1981,24,610-613), anti-inflammatory (J.Org.Chem.2001,72,1043-1046.), anti-obesity (Med.Chem.Comm 2013,4,456-462), herbicide (Organic Chemistry, 2004, 24, 1563-1568), phosphodiesterase inhibitor (J.Med.Chem.1997, 40, 4372-4377) and other activitie...

AI Technical Summary

Problems solved by technology

[0011] Although there are many synthetic methods, there are one or several disadvantages, such as high reaction temperature, many by-products, poor substrate universality, and cumbersome post-treatment, etc.

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