Fluorine-containing aromatic amino acids

Abstract

The light emitted when pion irradiated glucose is dissolved in luminol solution has been found to be proportional to the pion beam depth dose distribution in water as determined by a TE ionisation chamber. The lyoluminescence of glucose overlaps very closely with the response profile of the ionisation chamber to the 170 MeV/c Ir--mesons giving a Bragg peak to plateau ratio of 3 : 1. In comparison, the thermoluminescence response of LiF (TLD-700) to pions has been found to deviate significantly from this ratio. The close tissue equivalence of glucose, non-toxicity and its excellent lyoluminescent retention properties are important advantages over currently used dosemeters in clinical pion therapy, especially when direct in v i m measurements are considered.Pion doses ranging between 0.5 Gy (50 rad) and 30 Gy (3000 rad) were measured with an accuracy *s0/o and reproducibility 3-5%.

Selective Fluorinations by Reagents Containing the OF Group

“…160 Yagupolskii reviewed the synthesis of optically active aromatic amino acids mainly phenyl alanine and tyrosine where the aromatic fluorine was introduced with acetyl and other hypofluorites. 161 In 1992 Wilkinson published a review in this journal describing many fluorinating methods with a respectable proportion devoted to hypofluorites including CsSO 4 F. 162 Recently Resnati wrote a review which concentrated mainly on the synthesis and bioactivity of chiral fluorine-containing compounds and described electrophilic fluorination procedures with F 2 , CF 3 OF, and AcOF. Finally two books which are of great help to the fluoroorganic community should also be mentioned.…”

“…Mann covered selected literature dealing with hypofluorites, while Firnau concentrated on the synthesis of 18 F-containing compounds and their synthesis with AcOF . Yagupolskii reviewed the synthesis of optically active aromatic amino acids mainly phenyl alanine and tyrosine where the aromatic fluorine was introduced with acetyl and other hypofluorites .…”

Fluorine-containing 2,4-dioxo acids in the synthesis of heterocyclic compounds

“…The reaction of pentafluorobenzoylpyruvic acid (1j) with ethanolamine yields 3-pentafluorobenzoylmethylidenemorpholin-2-one (18). 41,42 When refluxed in DMSO, the morpholinone 18 undergoes cyclisation to form 7,8,9,10-tetrafluoro-4-oxo-1,2,4,6-tetrahydro [1,4]oxazino[4,3-a]-4-quinolone (19). Treatment of compound 19 with an aqueous KOH solution affords potassium 5,6,7,8-tetrafluoro-1-(2-hydroxyethyl)-4-quinolone-2carboxylate (20).…”

Synthesis of γ-fluoro-α-amino acids by Claisen rearrangement

“…Particularly, synthesis of fluorinated amino acids and derived peptides became a matter of intense research [6][7][8][9][10][11][12][13][14][15][16][17].…”