SYNTHESES FOR 2-AMINO AND 2-MERCAPTO-2H-1,4-BENZOXAZIN-3(4H)-ONE AND 2H-1,4-BENZOTHIAZIN-3(4H)-ONE AS AZA AND THIO ANALOGS OF THE NATURAL PRODUCT BLEPHARIGENIN

2-Amino-2H-1,4-benzoxazin-3(4H)-one 3, 2-amino-2H-1,4-benzothiazin-3(4 H)-one 4, 2-mercapto-2H-1 ,4-benzoxazin-3(4H)-one 7, and 2-mercapto-2H -1,4-benzothiazin-3(4H)-one 8 representing aza and thio analogues of t he natural product's aglucone Blepharigenin (2-hydroxy-2H-1,4-benzoxaz in-3(4H)-one) from Gramineae and Acanthaceae species have been synthes ized for the first time from their 2-bromo precursors 1 and 2. Attempt s to similarly prepare the 4-hydroxy derivatives of 7 and 8, which wou ld represent new thio analogues of the naturally occurring cyclic hydr oxamic acid, 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one, have failed.