title: Synthesis and antifungal activities of novel 5-amino-6-arylamino-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one derivatives.
abstract: A novel approach was developed to regioselectively synthesize new 5-amino-6-arylamino-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one 5 derivatives via a tandem aza-Wittig and annulation reactions of iminophosphorane 2, aromatic isocyanates, and hydrazine in 52-92% isolated yields. The compounds 5 reacted with triethyl orthoformate to give 1,8-2H-pyrazolo[3,4-d][1,2,4]triazolo[1,5-a]pyrimidin-4-ones 6 in good yields (62-94%). Their structures were clearly confirmed by spectroscopy data (IR, (1)H NMR, MS), elemental analysis, or X-ray diffraction crystallography. The results of preliminary bioassay indicated that the compounds 5 and 6 possessed high antifungal activity against Botrytis cinerea Pers and Sclerotinia sclerotiorum. Compounds 5 showed much better antifungal activities when R was Me instead of PhCH 2. Especially, compounds 6c, 6g, and 6i inhibited Sclerotinia by 100% at the concentration of 50 mg/L and by 83, 83, and 82% at the dosage of 10 mg/L, respectively.
authors.affiliation: College of Chemistry and Chemical Engineering, University of South China, 28 Changsheng Road Hengyang, Hunan 421001, People's Republic of China. hqwang2001cn@yahoo.com.cn
authors.forename: Hong-Qing
authors.initials: HQ
authors.lastname: Wang
authors.forename: Wei-Pimg
authors.initials: WP
authors.lastname: Zhou
authors.forename: Yu-Yuan
authors.initials: YY
authors.lastname: Wang
authors.forename: Can-Rong
authors.initials: CR
authors.lastname: Lin
mesh_terms: D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D001203:Ascomycota / Q000187:drug effects; D020171:Botrytis / Q000187:drug effects; D003460:Crystallization; D018360:Crystallography, X-Ray; D015394:Molecular Structure; D011720:Pyrazoles / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D014230:Triazoles / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D011720:Pyrazoles; C477655:Pyrazolotriazolopyrimidine; D011743:Pyrimidines; D014230:Triazoles; C014175:pyrazolo(3,4-d)pyrimidine