Tyrosine analogues

The fluorescence decay parameters of tyrosine and several tyrosine analogues at neutral pH are listed in Table 1.2. Tyrosine zwitterion and analogues with an ionized a-carboxyl group exhibit monoexponential decay kinetics. Conversion of the a-carboxyl group to the corresponding amide results in a fluorescence intensity decay that requires at least a double exponential to fit the data. While not shown in Table 1.2, protonation of the carboxyl group also results in complex decay kinetics.(38)... 

Table 1.2. Fluorescence Decay Parameters for Tyrosine and Tyrosine Analogues...

W. R. Laws, J. B. A. Ross, H. R. Wyssbrod, J. M. Beechem, L. Brand, and J. C. Sutherland, Time-resolved fluorescence and H NMR studies of tyrosine and tyrosine analogues Correlation of NMR-determined rotamer populations and fluorescence kinetics, Biochemistry 25, 599-607 (1986). 

An interesting comparison can be made looking at the a- and (5-tetralin derivatives entries—15/16 and —17 in Table 1 which can be regarded as cyclic confor-mationally constrained analogues of phenylglycine and phenylalanine. In an interesting study, 6-hydroxy-2-aminotetralin-2-carboxylic acid 12 (Hat) has been incorporated as a conformationally constrained tyrosine analogue into S-opioid receptor selective tetrapeptides.114 15 Whereas entry 15, the (S)-a-tetralin deriva-... 

Wang, D. and Cole, P. A. (2001) Protein tyrosine kinase Csk-catalyzed phosphorylation of Src containing unnatural tyrosine analogues. /. Am. Chem. Soc. 123, 8883-8886. 

Certain aromatic analogues of natural amino acids can be used as potential fluorescent probes of peptide structure and dynamics in complex environments. The research team of M.L. McLaughlin undertook the gram scale synthesis of racemic 1- and 2-naphthol analogues of tyrosine. The synthesis of the 1-naphthol tyrosine analogue started with the Gattermann formylation of 1-naphthol using the Adams modification to afford the formylated product 4-hydroxy-1-naphthaldehyde in 67% yield. 

Yokomatsu, T., Minowa. T.. Murano. T.. and Shibuya, S., Enzymatic desymmetrization of prochiral 2-benzyl-l,3-propanediol derivatives. A practical chemoenzymatic synthesis of novel phosphorylated tyrosine analogues. Tetrahedron. 54, 9341, 1998. 

PHE016 phenylboronic acid anticancer tyrosine analogue 1958JACS80 835... 

CUSHMAN M, NAGARATHMAN D, BURG D L and GEAHLEN R L (1991) Synthesis and protein-tyrosine kinase inhibitory activity of flavonoids analogues Journal cjf Medicinal Chemistry 34, 798-806. 

Figure 1 Structural formulas of cyclic analogues of phenylalanine and tyrosine.

Several reports have been made of a successful catalyzed addition/ substitution reaction resulting in direct attachment of phosphorus to aromatic rings. The preparation of mixed triarylphosphines has been accomplished by the reaction of tin- or silicon-substituted diphe-nylphosphines with aryl halides catalyzed by palladium reagents.74 A similar transformation has also been reported using nickel catalysis.75 The addition/substitution of diphenylphosphine to triflate functionalized phenolic linkages has been of use for the preparation of substances as analogues of tyrosine-related amino acid derivatives, accomplished with catalysis by palladium acetate (Equation 4.29).76... 

The hydrolytic accessibility of the ester bond in pTyr 1 (Scheme 1) to cellular protein-tyrosine phosphatases motivated numerous research groups to develop phosphatase-resistant bioisosteric analogues. It was soon recognized that the... 

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