Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... The total deprotection of N,N′-bis-Boc guanidines using SnCl 4 proceeds smoothly in ethyl acetate at room temperature and leads to the easily isolable corresponding guanidinium chlorides. ... The total deprotection of N,N′-bis-Boc guanidines using SnCl 4 proceeds ...