Clean synthesis of novel spiro[indene-2,2′-[1,3,5]-oxathiazine]-1,3-diones in water

In this work, we have designed an efficient and convenient method for the synthesis of novel Spiro [indene-2,2'-[1,3,5]oxathiazine]-1,3-diones by the one-pot, three component condensation of tetra methyl guanidine, ninhydrin, and isothiocyanates in water. Easy purification, green reaction conditions, easy performance and good yields are some advantages of this procedure. (C) 2017 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.