Pyrrolidine-modified and 6-substituted analogs of nicotine: A structure—affinity investigation
摘要:
Because the structural requirements for the binding of nicotine to central nicotine receptors remain largely uninvestigated, we undertook a systematic investigation of pyrrolidine ring-opened analogs. This led to a subsequent investigation of related conformationally restricted derivatives of these analogs. The results are reported relative to the binding of several well-known and widely used nicotine receptor ligands. Although none of the ring-opened analogs binds with higher affinity than (-)nicotine (K-i = 2.3 nM), 3-(N-methyl-N-ethylaminomethyl)pyridine (12a; K-i = 28 nM) binds with significant affinity. A conformationally restricted analog of 12a, N-methyl [2,7]naphthyridine 30b (K-i = 18 nM), binds with similar affinity. 6-Substitution of 12a and racemic nicotine seems to be tolerated when the substituent is halogen or methyl. In functional studies (hypolocomotion and antinociception in mice; stimulus generalization in nicotine-trained rats) 30b retains nicotine-like properties. Several of the 6-substituted compounds were 2 to 20 times more potent than (+/-)nicotine. Although the intact pyrrolidine ring of nicotine appears important for optimal affinity, its pre presence is not an absolute requirement for activity, and 6-position substitution of the pyridine nucleus can influence both binding and functional activity.
Pyrrolidine-modified and 6-substituted analogs of nicotine: A structure—affinity investigation
摘要:
Because the structural requirements for the binding of nicotine to central nicotine receptors remain largely uninvestigated, we undertook a systematic investigation of pyrrolidine ring-opened analogs. This led to a subsequent investigation of related conformationally restricted derivatives of these analogs. The results are reported relative to the binding of several well-known and widely used nicotine receptor ligands. Although none of the ring-opened analogs binds with higher affinity than (-)nicotine (K-i = 2.3 nM), 3-(N-methyl-N-ethylaminomethyl)pyridine (12a; K-i = 28 nM) binds with significant affinity. A conformationally restricted analog of 12a, N-methyl [2,7]naphthyridine 30b (K-i = 18 nM), binds with similar affinity. 6-Substitution of 12a and racemic nicotine seems to be tolerated when the substituent is halogen or methyl. In functional studies (hypolocomotion and antinociception in mice; stimulus generalization in nicotine-trained rats) 30b retains nicotine-like properties. Several of the 6-substituted compounds were 2 to 20 times more potent than (+/-)nicotine. Although the intact pyrrolidine ring of nicotine appears important for optimal affinity, its pre presence is not an absolute requirement for activity, and 6-position substitution of the pyridine nucleus can influence both binding and functional activity.
Molecular determinants of the platelet aggregation inhibitory activity of carbamoylpiperidines
作者:Zixia Feng、Ramachander Gollamudi、Elwood O. Dillingham、Stephen E. Bond、Beverly A. Lyman、William P. Purcell、Robert J. Hill、Walter A. Korfmacher
DOI:10.1021/jm00094a004
日期:1992.8
Compound 3a was resolved into (+) and (-) enantiomers and a meso (0) diastereomer using fractional crystallization, diastereomeric tartrate formation, and chiral HPLC. Compared to (-)-3a, the (+) isomer was 15 times more potent when ADP was the agonist and 19 times more active when collagen was used as the agonist. Molecular modeling of R,R- and S,S-3a using the SYBYL program was used to examine their interactions
Design and Synthesis of Piperidine-3-carboxamides as Human Platelet Aggregation Inhibitors
作者:Xiaozhang Zheng、Somna R. Salgia、Walter B. Thompson、Elwood O. Dillingham、Stephen.E. Bond、Zixia Feng、K. Ram Prasad、Ram Gollamudi
DOI:10.1021/jm00001a023
日期:1995.1
structure-activity analysis was carried out using eight 1-alkyl(aralkyl)nipecotamides (type 5), 33 bis-nipecotamidoalkanes and aralkanes (type 6), and 7 N,N'-bis(nipecotoyl)-piperazines (type 7) as inhibitors of human plateletaggregation. Steric factors played an important role in determining the activity of type 5 compounds possessing an an appropriate degree of hydrophobic character. Types 6 and 7 compounds were
Because the structural requirements for the binding of nicotine to central nicotine receptors remain largely uninvestigated, we undertook a systematic investigation of pyrrolidine ring-opened analogs. This led to a subsequent investigation of related conformationally restricted derivatives of these analogs. The results are reported relative to the binding of several well-known and widely used nicotine receptor ligands. Although none of the ring-opened analogs binds with higher affinity than (-)nicotine (K-i = 2.3 nM), 3-(N-methyl-N-ethylaminomethyl)pyridine (12a; K-i = 28 nM) binds with significant affinity. A conformationally restricted analog of 12a, N-methyl [2,7]naphthyridine 30b (K-i = 18 nM), binds with similar affinity. 6-Substitution of 12a and racemic nicotine seems to be tolerated when the substituent is halogen or methyl. In functional studies (hypolocomotion and antinociception in mice; stimulus generalization in nicotine-trained rats) 30b retains nicotine-like properties. Several of the 6-substituted compounds were 2 to 20 times more potent than (+/-)nicotine. Although the intact pyrrolidine ring of nicotine appears important for optimal affinity, its pre presence is not an absolute requirement for activity, and 6-position substitution of the pyridine nucleus can influence both binding and functional activity.