78562-03-5Relevant articles and documents
Vinylation of α-Aminoazoles with Triethylamine: A General Strategy to Construct Azolo[1,5-a]pyrimidines with a Nonsubstituted Ethylidene Fragment
Gao, Qinghe,Sun, Zhenhua,Xia, Qinfei,Li, Ruonan,Wang, Wenlong,Ma, Siwei,Chai, Yixin,Wu, Manman,Hu, Wei,ábrányi-Balogh, Péter,Keserü, Gy?rgy M.,Han, Xinya
supporting information, p. 2664 - 2669 (2021/04/12)
A new general synthesis of pharmaceutically important azolo[1,5-a]pyrimidines starting from widely available 3(5)-aminoazoles, aldehydes, and triethylamine is developed. The key is to enable the vinylation reaction that allows the in situ generation of elusive acyclic enamines and the subsequent annulation reaction to occur. This direct and practical strategy is capable of constructing a range of 5,6-unsubstituted pyrazolo[1,5-a]pyrimidines and [1,2,4]triazolo[1,5-a]pyrimidines. More importantly, this protocol provides a concise synthetic route to prepare the clinically used zaleplon.
Synthesis of a new series of pyrazolo[1,5-a]pyrimidines structurally related to zaleplon
Baraldi, Pier Giovanni,Fruttarolo, Francesca,Tabrizi, Mojgan Aghazadeh,Romagnoli, Romeo,Preti, Delia,Ongini, Ennio,El-Kashef, Hussein,Carrion, Maria Dora,Borea, Pier Andrea
, p. 355 - 361 (2008/04/12)
(Chemical Equation Presented) The reaction between 3-(dimethylamino)/3,3- bis(methylthio)-1-(substituted)prop-2-en-1-ones and 4-substituted-5-amino-1H- pyrazoles afforded new pyrazole[1,5-a]pyrimidines structurally related to Zaleplon. The chemical modifications introduced at the 3-, 5-, and 7-positions of the bicyclic structure revealed new promising candidates for the treatment of sleep disorders.
