Glycine phthaloyl

O. A. Salach, S. Hadad, A. Haj-Yehia, S. Sussan, M. Bialer, Comparative Pharmacokinetic and Pharmacodynamic Analysis of Phthaloyl Glycine Derivatives with Potential Antiepileptic Activity , Pharm. Res. 1994, 11, 1429-1434. 

Figure 12.1 Dirhodium catalysts (TCPTTL, N tetrachlorophthaloyl (S) tert leucinate TCPTAD, N tetrachloro phthaloyl (S) (1 adamantyl)glycinate).

The ester enolate Claisen rearrangement of (Z)-crotyl /V-tm-Boc-glycinate has been applied to the synthesis of lactone hydrochloride 4, the hydrolysis product of the amanita mushroom toxins a- and / -amanitin487. The rearrangement and the iodolactonization of the A -phthaloyl derivative are the stereocontrolling steps in this reaction sequence. 

A soln. of phenacyl phthaloylglycinate and 2 moles of Na-thiophenoxide in dimethylformamide allowed to stand 15 min. at room temp. Na-phthaloyl-glycinate. Y 99%.—This procedure is ideally suited for cleaving protected carboxyl functions in synthetic sequences involving sensitive molecules such as peptides and penicillins. F. e. s. J. C. Sheehan and G. D. Daves, Jr., J. Org. Chem. 29, 2006 (1964). 

Little is known about the direct oxidation of amino acid derivatives. Although an a-acetoxy derivative can be prepared from hippuric acid by treatment with lead tetraacetate (99) this reaction is not applicable to N-phthaloyl- or N-benzyloxycarbonyl-glycine. Anodic oxidation of acetamidomalonic acid monoester in alcohol yielded the ot-alkoxy-a-acetamino acetic acid, while in acetic acid the corresponding oc-acetoxy compound was obtained (186). The oxidation of optically active N-salicylidene-alanine cobalt (III) complexes has been studied as a model reaction for enzymatic deamination of a-amino acids, and found to yield the corresponding diastereomeric a-hydroxy alanine complexes (118). 

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