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• 603-35-0 triphenylphosphine 

Relevant academic research and scientific papers

Regioselective synthesis and bioactivity of new 5-amino-6- Arylamino-pyrazolo[3,4-d]-pyrimidin-4(5H)-one derivatives

A novel approach to regioselective synthesis of new 5-amino-6-arylamino-1H- pyrazolo[3,4-d]pyrimi- din-4(5H)-one 5 derivatives via a tandem aza-wittig and annulation reaction of iminophosphorance 2, aromatic isocyanates and hydrazine in 69.6-94.7% isolated yields is reported. The compound 5 reacted with triethyl orthoformate to give compound 6 in good yield (65.8-82.8%). Their structure was clearly confirmed by spectroscopy data (IR, 1H NMR, MS, elemental analysis) and the results of preliminary bioassay indicated that compounds 5 and 6 possess high antifungal activity against Botrytis cinerea Pers and Sclerotinia sclerotiorum, and compound 5h showed 100, 96.4, and 90.2% inhibitory rate to Botrytis cinerea Pers, Pyricularia oryzae, and Sclerotinia sclerotiorum at the concentration of 50 mg/L. The antifungal activities of compound 6 were generally higher than those of compound 5.

Synthesis and antifungal activities of novel 5-amino-6-arylamino-1H- pyrazolo[3,4-d]pyrimidin-4(5H)-one derivatives

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, 1H 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 PhCH2. 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.

A novel synthesis and herbicidal activity of fluorine-containing pyrazolo[3,4-d]pyrimidin-4-one derivatives

The 6-(4-alkoxycarbonylalkoxy)phenoxy-3-alkylthio-5-(fluoro-substituted)phenyl-1-phenylpyrazolo[3,4-d]pyrimidin-4-ones 6 have been successfully synthesized via a tandem aza-Wittig and annulation reactions of the corresponding iminophosphorances 4, aromatic isocyanate, and substituted phenols 2 in 59-69% isolated yields using actonitrile as solvent. These novel compounds 6 could be oxidized to sulfones 7 by hydrogen peroxide in satisfactory yields (57-93%). Their structures were clearly verified by spectroscopic data (IR, 1H NMR, 13C NMR, MS, Elemental analysis or X-ray diffraction crystallography). The results of preliminary bioassay indicated that these compounds possess herbicidal activity against the root of rape and barnyard grass.

Versatile synthesis and fungicidal activities of 6-amino-3-alkylthio-1,5- dihydro-1-phenyl-pyrazolo [3,4-d]pyrimidin-4-one derivatives

A series of new 6-alkylamino-3-alkylthio-1-phenyl-1H-pyrazolo[3,4-d] pyrimidin-4(5H)-one derivatives 5 and 6 have been rapidly synthesized by a novel solution-phase regioselective synthetic method. Treatment of pyrazole o-aminoester 1 with dibromotriphenylphosphorane gave iminophosphorane 2, which underwent a aza-Wittig reaction with phenyl ioscyanate to provide the carbodiimide 3. The latter intermediate reacted with alkylamines and regioselectively provided the 1,5-dihydro-pyrazolo[3,4-d]pyrimidin-4-one derivatives 5 and 6, some of which exhibited good fungicidal activity.