Tryptophan carbobenzyloxy

Commercially supplied carbobenzyloxy-amino acids were used in this study (Carbobenzyloxyglycine, 99%, N-(Carbobenzyloxy)-L-phenylalanine, 99% and N-Carbobenzyloxy-L-tryptophan, 99%) and were purchased from Aldrich. Deionized water and commercial absolute ethanol were used as solvents. 

A parallel study [94] was performed by the same authors on the retention of model compounds (tryptophan, erythro- and t/ireo-P-methyltryptophan, A-carbobenzyloxy-tryptophan, A-(3,5-dinitro-2-pyridyl)-tryptophan, l-[5-chloro-2-(methylamino) phenyl]-l,2,3,4-tetrahydroisoquinoline, and y-phenyl-y-butyrolactone) on a ristocetin A-based CSP, using the three RP, POM, and NP elution systems. Also, in this case, the natural logarithms of the retention factors (In k) of the investigated compounds depended linearly on the inverse of temperature (1 /T). 

In the process of lactonization of L-tryptophan or its DNP-derivative a second asymmetric center is formed, probably stereoselectively, by induction from the existing center. Opening of this DNP-lactone and application of Hudson s rule (cf. Witkop, 1956 Vanderhaeghe and Parmentier, 1961) has so far pointed to the Dq structure for the spirooxindole-/3-carbon (Ramachandran, 1961), but this preliminary observation on a colored lactone derivative must await conformation from, e.g., a carbobenzyloxy lactone derivative. 

C18H38S propyl pentadecyl sulfide 66292-32-8 22.50 0.8458 2 31410 C19H18N204 Na-carbobenzyloxy-L-tryptophan 7432-21-5 25.00 1.2576 2... 

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