Isothiazoles chemical properties

Chemical Properties. - WQuatemization of Isothiazoles. 3-Chloroisothiazole is quaternized by FSOsMe the salt is then treated with MeNH2 and passed through an ion-exchanger (Cl ) to give (19 R = R = Me Z = Cl). Other... 

Synthesis of Isothiazoles, Isothiazolines, and Isothiazolidines 151 From amidoketones and hydrogen sulphide (Type A C-C-C-N + S) 151 From iminonitriles and mercaptoacetic acid derivatives (Type B C-C-N + S-C) 151 From cyclisation of enaminothiones (Type C N-C-C-C-S) 152 From sulphonamidoacetates and diethyl oxalate (N-S-C + C-C) 152 From ketenes and sulphur di-imides (N-S-C + C-C) 152 Physical Properties of Isothiazoles and Isothiazolines 152 Chemical Properties of Isothiazoles, Isothiazolines, and Isothiazolidines 153... 

Meso-ionic Isothiazoles.— The synthesis and chemical properties of novel meso-ionic compounds of the dehydrodithizone (2,3-diphenyltetrazolium 5-sulphide) family derived from pyrazole, isothiazole, and isoxazole have been described. The member (28) of the isothiazole series is accessible from 3-methylisothiazole... 

The n.m.r. spectra of the isothiazolo[5,l-e]isothiazoles (82) show magnetic equivalence of ring protons or substituents at the pairs of sites N-l/N-6, C-2/C-5, and C-3/C-4, thus demonstrating that, in solution, the compounds possess real or time-averaged symmetry. Their chemical properties resemble those of enamines and pyrroles. Their electron-rich nature, suggested by n.m.r. chemical... 

Chemical Properties of Isothiazoles, Isothiazolines, and Iso-thiazolidines. - Diazotisation and subsequent azo coupling of various 5 amino-3 l-disubstituted isothiazoles has been reported. 

The intensified activity in the study of the chemistry of isothiazole, noted in the previous Report, has been sustained, possibly with an emphasized interest in condensed ring-systems. Now that numerous syntheses of isothiazoles are available, the careful and detailed investigation of both the physical and chemical properties of this ring-system, and its correlation with related structures, are particularly timely. The possible involvement of isothiazole derivatives in the biosynthetic pathway to penicillins and cephalosporins is a suggestion of exceptional interest (see ref. 43, below) that will no doubt stimulate further significant work. 

---