Reactions of Substituted Xanthotoxin with Nitriles and Hydrazines
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4 B r o m o x a n t h o t o x i n r e a c t s w i t h c y a n o a c e t a m i d e t o f o r m 4 b r o m o 5 , 6 d i h y d r o x a n t h o t o x i n , w h i c h o n h y d r o l y s i s w i t h c o l d h y d r o c h l o r i c a c i d l e a d s t o t h e f o r m a t i o n o f c y a n o a c e t i c a c i d d e r i v a t i v e , b u t h y d r o l y s i s b y b o i l e d h y d r o c h l o r i c a c i d g i v e s t h e a c e t i c a c i d d e r i v a t i v e . T h i o , a n d 4 n i t r o x a n t h o t o x i n r e a c t s w i t h m a l o n o n i t r i l e i n p r e s e n c e o f p i p e r i d i n e b y a d d i t i o n t o g i v e t h i o a n d 4 n i t r o 5 , 6 d i h y d r o x a n t h o t o x i n 5 [ l ' , 3 , , 3 ' t r i c y a n o 2 a m i n o p r o p e n e ( 2 ) ] r e s p e c t i v e l y , w h i l e i n p r e s e n c e o f a m m o n i a l e a d s t o t h e f o r m a t i o n o f 5 m a l o n o n i t r i l e d e r i v a t i v e s . T h e r e a c t i o n o f h y d r a z i n e a n d p h e n y l h y d r a z i n e w i t h t h i o a n d 4 b r o m o t h i o x a n t h o t o x i n l e a d s t o t h e f o r m a t i o n o f t h e h y d r a z o n e s . A l s o t h i o a n d 4 b r o m o t h i o x a n t h o t o x i n r e a c t s w i t h a n h y d r o u s a l u m i n i u m c h l o r i d e i n b e n z e n e b y c l e a v a g e o f t h e f u r a n r i n g a n d t h e f o r m a t i o n o f 6 ( l , 2 d i p h e n y l e t h y l ) 7 , 8 d i h y d r o x y t h i o c o u m a r i n a n d 5 b r o m o 6 ( 1 , 2 d i p h e n y l e t h y l ) 7 , 8 d i h y d r o x y t h i o c o u m a r i n , r e s p e c t i v e l y .
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