Tritylamino acid

L Zervas, DM Theodoropoulus. IV-Tritylamino acids and peptides. A new method of peptide synthesis. J Am Chem Soc 78, 1359, 1956. 

N-Tritylamino acids. Direct reaction of trityl chloride with amino acids provides N-trityl derivatives in low yield. A superior route to these derivatives involves reaction of trimethylsilyl esters of N-trimethylsilylamino acids with trityl chloride in refluxing chloroform, which provides the N-protected amino acids in 88-92% yield. Trimethylsilyl-protected hydroxyl or thiol groups are not cleaved under these conditions.1... 

Alsina, J., Giralt, E., and Albericio, F. (1996) Use of A-tritylamino acids and PyAOP for the suppression of diketopiperazine formation in Fmoc/ Bu solid-phase peptide synthesis using alkoxybenzyl ester anchoring linkages. Tetrahedron Lett. 37, 4195-4198. 

N-ProtecUve group. Although the trityl group has received some consideration for the N-protection of amino acids, a serious limitation is that, with the exception of the glycine derivative, the p-nitrophenyl esters of N-tritylamino acids do not couple with amino acid esters. ... 

Replacement of three fluorine atoms in cyanuric fluoride 55 was applied for construction biologically active molecules of deazapurine type [95]. Cyanuric fluoride mediated reaction of chiral Na-tritylamino acids leads to the corresponding acyl fluorides 155 which are powerful acylating agents for peptide synthesis... 

Karygiannis G, Athanassopoulos C, Mamos P, Karamanos N, Papaionnou D, Francic GW (1998) Preparation and properties of enantiomericaUy pure Na-tritylamino acid fluorides. Acta Chem Scand 52 1144-1150... 

N- Trityl a-amino acids.1 TrBr is markedly superior to TrCl for tritylation of a-amino acids. The reaction of the acids with TrBr (2 equiv.) and (excess) triethyl-amine in CHC13/DMF (2 1) provides the N-tritylamino trityl ester, which is then hydrolyzed in situ with methanol at 50°. Yields are 80-86%. 

Z)-2-(2-tert-Butoxycarbonylprop-2-oxyimino)-2-(2-tritylamino-thiazol-4-yl)acetic acid Ceftazidime... 

A similar sequence to those described above converted phenylalanine 5.76) to N-tritylcyclohexyl derivative 5.94. This reaction sequence took a novel turn when 5.94 was converted to a phosphite ester (5.95). Treatment with sodium hydride gave a very novel, highly functionalized ylid that reacted with the keto-ester shown to give 5.96. Basic hydrolysis led to 5-(N-tritylamino)-6-cyclohexyl-2-dimethyl-methylene-4-oxohexanoic acid, 5.97. 

Treatment of 2,5-anhydro-3,4-di-0-benzyl-1 -deoxy-1 -tritylamino-D-glucitol with mesyl chloride, tosic acid-methanol, triethylamine then hydrogen-palladium catalyst affords the 1,6-imino-bridged derivative The reaction of l,2 5,6-dianhydro-3,4-0-isopropylidene-D-mannitol with ben-zylamine followed by deprotection leads only to the seven-membered azepane 52 in high yield. Other l,2 5,6-dianhydro-3,4-0-isopropylidene hexitols gave similar results. No six-membered ring products were detected as is the case with 1,2 5,6-dianhydro-3,4-di-( -benzyl-D-mannitol (see Vol. 28, p. 230, ref. 63). ... 

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