Ultrasound-assisted synthesis of 2-amino-1,3,4-oxadiazoles through NBS-mediated oxidative cyclization of semicarbazones. - Borsoi, Ana Flávia; Coldeira, Mateus Emanuel; Pissinate, Kenia; Macchi, Fernanda Souza; Basso, Luiz Augusto; Santos, Diógenes Santiago; Machado, Pablo (Synthetic Communications, 2017)