Exploration of N-phosphonoalkyl-, N-phosphonoalkenyl-, and N-(phosphonoalkyl)phenyl-spaced .alpha.-amino acids as competitive N-methyl-D-aspartic acid antagonists
摘要:
A series of N-substituted alpha-amino acids containing terminal phosphonic acid groups has been synthesized as potential N-methyl-D-aspartate (NMDA) receptor antagonists. NMDA receptor affinity was determined by displacement of a known ligand ([H-3]CPP) from crude rat brain synaptic membranes; an antagonist action was demonstrated by the inhibition of glutamate-induced accumulation of [Ca-45(2+)] in cultured rat cortical neurons. Receptor affinity was significantly correlated with antagonist activity (Figure 1). Moderate affinity (IC50 = 1-2-mu-M) was retained for analogues (31 and 32, Table 1; and 59 and 66, Table II) with reduced flexibility in their phosphonate side chains and is consistent with entropy playing a role in determining receptor affinity. Modeling studies suggest a folded conformation that brings the distal phosphonic acid group into close proximity with the alpha-carboxylate is required for binding. Each of the active analogues possess entropy-limiting features (double bonds, phenyl rings) in their side chains that allows the superposition of their key NH2, alpha-COOH, and distal PO3H2 groups with those of known competitive antagonists. Affinity decreased for analogues with alpha-carbon substitution, presumably because the alpha-substituent inhibits the folding of these structures into a bioactive conformation and occupies receptor-excluded volume. A complete description of the NMDA antagonist pharmacophore model is provided in a companion paper. 1
Exploration of N-phosphonoalkyl-, N-phosphonoalkenyl-, and N-(phosphonoalkyl)phenyl-spaced .alpha.-amino acids as competitive N-methyl-D-aspartic acid antagonists
摘要:
A series of N-substituted alpha-amino acids containing terminal phosphonic acid groups has been synthesized as potential N-methyl-D-aspartate (NMDA) receptor antagonists. NMDA receptor affinity was determined by displacement of a known ligand ([H-3]CPP) from crude rat brain synaptic membranes; an antagonist action was demonstrated by the inhibition of glutamate-induced accumulation of [Ca-45(2+)] in cultured rat cortical neurons. Receptor affinity was significantly correlated with antagonist activity (Figure 1). Moderate affinity (IC50 = 1-2-mu-M) was retained for analogues (31 and 32, Table 1; and 59 and 66, Table II) with reduced flexibility in their phosphonate side chains and is consistent with entropy playing a role in determining receptor affinity. Modeling studies suggest a folded conformation that brings the distal phosphonic acid group into close proximity with the alpha-carboxylate is required for binding. Each of the active analogues possess entropy-limiting features (double bonds, phenyl rings) in their side chains that allows the superposition of their key NH2, alpha-COOH, and distal PO3H2 groups with those of known competitive antagonists. Affinity decreased for analogues with alpha-carbon substitution, presumably because the alpha-substituent inhibits the folding of these structures into a bioactive conformation and occupies receptor-excluded volume. A complete description of the NMDA antagonist pharmacophore model is provided in a companion paper. 1
A simple and mild methodology for the directsynthesis of alkynylphosphonates is presented. The reaction of a variety of terminalalkynes with dialkyl phosphites in the presence Cu2O (14 mol %) led to the formation of the corresponding alkynylphosphonates in good to excellent yields. Reactions are performed under air, in acetonitrile as solvent, and in the absence of base or ligand additives. This
Exploration of N-phosphonoalkyl-, N-phosphonoalkenyl-, and N-(phosphonoalkyl)phenyl-spaced .alpha.-amino acids as competitive N-methyl-D-aspartic acid antagonists
作者:Christopher F. Bigge、Graham Johnson、Daniel F. Ortwine、James T. Drummond、Daniel M. Retz、Laura J. Brahce、Linda L. Coughenour、Frank W. Marcoux、Albert W. Probert
DOI:10.1021/jm00086a005
日期:1992.4
A series of N-substituted alpha-amino acids containing terminal phosphonic acid groups has been synthesized as potential N-methyl-D-aspartate (NMDA) receptor antagonists. NMDA receptor affinity was determined by displacement of a known ligand ([H-3]CPP) from crude rat brain synaptic membranes; an antagonist action was demonstrated by the inhibition of glutamate-induced accumulation of [Ca-45(2+)] in cultured rat cortical neurons. Receptor affinity was significantly correlated with antagonist activity (Figure 1). Moderate affinity (IC50 = 1-2-mu-M) was retained for analogues (31 and 32, Table 1; and 59 and 66, Table II) with reduced flexibility in their phosphonate side chains and is consistent with entropy playing a role in determining receptor affinity. Modeling studies suggest a folded conformation that brings the distal phosphonic acid group into close proximity with the alpha-carboxylate is required for binding. Each of the active analogues possess entropy-limiting features (double bonds, phenyl rings) in their side chains that allows the superposition of their key NH2, alpha-COOH, and distal PO3H2 groups with those of known competitive antagonists. Affinity decreased for analogues with alpha-carbon substitution, presumably because the alpha-substituent inhibits the folding of these structures into a bioactive conformation and occupies receptor-excluded volume. A complete description of the NMDA antagonist pharmacophore model is provided in a companion paper. 1