1279558-76-7Relevant articles and documents
Mechanistic approach of the difference in non-enzymatic hydrolysis rate between the L and D enantiomers of no-carrier added 2-[18F] fluoromethyl-phenylalanine
Kersemans, Ken,Mertens, John,De Proft, Frank,Geerlings, Paul
, p. 80 - 85 (2011)
No-carrier added (n.c.a.) 2-[18F]fluoromethyl-l-phenylalanine was found to be very sensitive to hydrolysis in aqueous solutions. This problem was solved partially by the addition of calcium ions (0.04M), increasing the shelf-life to at least 6h. In this paper the defluorination reaction was studied in detail to elucidate its mechanism. Therefore, L and D enantiomers of 2-[18F]FMP and 4-[18F]FMP were synthesized, as well as 2-[18F]fluoromethyl-phenethylamine and 4-[18F] fluoromethyl-phenethylamine, both decarboxylated 'mimetic' molecules of the amino acid analogues. Radiosynthesis, using a customized Scintomics automatic synthesis hotboxthree module, resulted in a high overall yield and a radiochemical purity of >99%. The defluorination rates of all compounds were studied by HPLC. The L enantiomer of n.c.a 2-[18F]FMP defluorinated seven times faster than the D enantiomer and 2-[18F]fluoromethyl- phenethylamine. Both enantiomers of 4-[18F]FMP and 4-[ 18F]fluoromethyl-phenethylamine were stable. From these data, the reaction mechanism, involving two distinct intramolecular interactions, was derived. First, the interaction between the amine and the benzylic fluorine weakens the carbon-fluorine bond. Secondly, the formation of a second hydrogen bridge between the carboxyl group and one of the benzylic hydrogen atoms renders the fluorine atom even more susceptible to hydrolysis. The latter interaction induces an additional chiral center. The probability of its formation differs considerably between L and D enantiomers of n.c.a. 2-[18F]FMP, which explains the difference in hydrolysis rate. Copyright
NOVEL NON-SYSTEMIC TGR5 AGONISTS
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Page/Page column 92, (2018/02/28)
The present invention relates to tricyclic compounds of formula (I) and formula (II), or a pharmaceutically acceptable salt thereof. The present tricyclic compounds are useful non-sytemic TGR5 agonists that can be used to treat diabetic diseases in human. The present invention provides a pharmaceutical composition containing tricyclic compounds of formula (I) and formula (II) and a method of making as well as a method of using same in treating patients inflicted with metabolic disorders by administering same. The compounds of the present invention may be used in combination with additional anti-diabetic drugs.
Mechanistic approach of the difference in hydrolysis rate between the 2- and 4-isomers of no-carrier-added [18F]fluoromethyl-L-phenylalanine
Kersemans, Ken,Mertens, John,De Proft, Frank,Geerlings, Paul
experimental part, p. 220 - 223 (2012/05/20)
No-carrier-added (n.c.a.) 2-[18F]fluoromethyl-l-phenylalanine (2-[18F]FMP) was found to be very sensitive to hydrolysis in aqueous solutions. In this paper, the defluorination reaction was studied in detail to elucidate its mechanism
