Convergent Synthesis and Pharmacology of Substituted Tetrazolyl-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid Analogues
摘要:
The synthesis and pharmacological characterization of 1- and 2-alkyltetrazolyl analogues of (RS)-2-amino-3-[3-hydroxy-5-(2-methyl-2H-5-tetrazolyl)-4-isoxazolyl]propionic acid (2-Me-Tet-AMPA), a highly potent and selective agonist at AMPA receptors, are presented. A shorter and more convergent synthetic route than previously described, employing a new method for introducing the amino acid moiety, was developed for these derivatives. The 2-substituted isomers were selective agonists, and their activity correlated inversely with the size of the substituent. Structural explanations of the structure-activity relationship are provided.
A Straightforward and Highly Diastereoselective Access to Functionalized Monofluorinated Cyclopropanes <i>via</i> a Michael Initiated Ring Closure Reaction
synthesis of highly functionalized monofluorinated cyclopropanes based on a Michael Initiated RingClosure (MIRC) reaction has been developed. The addition of quaternary ammonium salts derived from ethyl bromofluoroacetate on a panel of electron deficient alkenes followed by cyclization gave rise to an efficient access to monofluorinated cyclopropanes with good yields and remarkable diastereoselectivity
High yielding synthesis of dehydroamino acid and dehydropeptide derivatives
作者:Paula M. T. Ferreira、Hernâni L. S. Maia、Luís S. Monteiro、Joana Sacramento
DOI:10.1039/a904730a
日期:——
By using a 4-dimethylaminopyridine (DMAP) catalysed reaction of β-hydroxyamino acid derivatives with tert- butyl pyrocarbonate [(Boc)2O], dehydroamino acid derivatives are obtained in high yields. The same methodology applied to dipeptides with a β-hydroxyamino acid residue gives the corresponding dipeptides with a dehydroamino acid residue.
Light switch: A photochromicagonist ATA‐3 (see scheme) of AMPAreceptors, arguably the most important class of ionotropic glutamate receptors, is shown to be subtype selective, activates the AMPAreceptor GluA2 in the dark, and is quickly turned off when irradiated with blue–green light. It can be used to effectively control neuronal activity in the mammalian brain.
Efficient synthesis of dehydroamino acid derivatives
作者:Paula M.T. Ferreira、Hernâni L.S. Maia、Luís S. Monteiro
DOI:10.1016/s0040-4039(98)02164-9
日期:1998.12
By using a DMAP catalysed reaction of β-hydroxyamino acid derivatives with tert-butylpyrocarbonate, the corresponding dehydroaminoacid derivatives were obtained in high yields.
The unique combination of Zn/LiCl allowed generation of reactive zinc enolate from ethyl dibromofluoroacetate. This fluorinated enolate reacts efficiently with a wide range of functionalized electron-deficient alkenes to afford the corresponding monofluorinated cyclopropylcarboxylates in good yields.