Synthesis of Hydroxydiisotyrosine by the Enolate Method The reaction sequence is illustrated in Scheme 2. The aryl bromide 16 represents a completely protected 2-hydroxy-5- bromophenylserine and can be prepared via 15 by the Evans method. 23 The palladium (0)- catalyzed coupling of 16 with the boronic acid 17 containing an unprotected aldehyde function gives rise to the biphenyl derivative 18. The stated reaction conditions must be ...
![2-(2-benzyloxy-5-bromophenyl)-[1,3]dioxane结构式](https://image.chemsrc.com/caspic/013/121124-96-7.png)
![4,4'-bis(benzyloxy)-3'-(1,3-dioxan-2-yl)-[1,1'-biphenyl]-3-carbonyl chloride结构式](https://image.chemsrc.com/caspic/332/146335-29-7.png)
![4,4'-dibenzyloxy-3-[(R,S)-2-(tert-butoxycarbonylamino)-2-methoxycarbonyl-1-oxoethyl]-3'-(1,3-dioxan-2-yl)biphenyl结构式](https://image.chemsrc.com/caspic/467/146335-30-0.png)
![4,4'-dibenzyloxy-3-[(R)-2-(tert-butoxycarbonylamino)-2-methoxycarbonyl-(R)-1-hydroxyethyl]-3'-(1,3-dioxan-2-yl)biphenyl结构式](https://image.chemsrc.com/caspic/429/146335-31-1.png)
![methyl (2S,3R)-2-((2S,4R)-5-(((benzyloxy)carbonyl)amino)-2-((tert-butoxycarbonyl)amino)-4-hydroxypentanamido)-3-(4,4'-bis(benzyloxy)-3'-((S)-2-(((benzyloxy)carbonyl)amino)-3-oxo-3-(perfluorophenoxy)propyl)-[1,1'-biphenyl]-3-yl)-3-hydroxypropanoate结构式](https://image.chemsrc.com/caspic/393/146388-29-6.png)
