K. Avasthi et al., A CONVENIENT AND GENERAL-SYNTHESIS OF ETHYLTHIO-1H-PYRAZOLO[3,4-D]PYRIMIDIN-1-YL)ALKANES AND THEIR REGIOISOMERS, Indian journal of chemistry. Sect. B: organic chemistry, including medical chemistry, 34(11), 1995, pp. 944-949
A convenient and general synthesis of methylthio-1H-pyrazolo[3,4-d]pyr
imidin-1-yl)alkane (9), ethylthio-2H-pyrazolo-[3,4-d]pyrimidin-2-yl)al
kane (10) and methylthio-2H-pyrazolo[3,4-d]pyrimidin-2-yl)alkane (11)
has been carried out by the reaction of 4,6-dimethylthio-1H-pyrazolo[3
,4-d]pyrimidine (3) and 1,omega-dibromoalkane (4;n=2-5).