Structure–Activity relationship of linear peptide Bu-His-DPhe-Arg-Trp-Gly-NH2 at the human melanocortin-1 and -4 receptors: histidine substitution
摘要:
Systematic substitution of His(6) residue using non-selective hMC4R pentapeptide agonist (Bu-His(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)- NH2) as the template led to the identification of Bu-Atc(6)(2-aminotetraline-2-carboxylic acid)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 which showed moderate selectivity towards hMC4R over hMC1R. Further SAR studies resulted in the discovery of Penta-5-BrAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 and Penta-5-Me(2)NMAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 which are potent hMC4R agonists and are inactive in hMC1R, hMC3R and hMC5R agonist assays. (C) 2002 Published by Elsevier Science Ltd.
Structure–Activity relationship of linear peptide Bu-His-DPhe-Arg-Trp-Gly-NH2 at the human melanocortin-1 and -4 receptors: histidine substitution
摘要:
Systematic substitution of His(6) residue using non-selective hMC4R pentapeptide agonist (Bu-His(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)- NH2) as the template led to the identification of Bu-Atc(6)(2-aminotetraline-2-carboxylic acid)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 which showed moderate selectivity towards hMC4R over hMC1R. Further SAR studies resulted in the discovery of Penta-5-BrAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 and Penta-5-Me(2)NMAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH2 which are potent hMC4R agonists and are inactive in hMC1R, hMC3R and hMC5R agonist assays. (C) 2002 Published by Elsevier Science Ltd.
Radiationless transitions of 1-(dimethylamino)naphthalene (1DMAN) and its 4-, 5-, 6-, and 7-methoxy derivatives having a twisted dimethylamino group in the Franck-Condon excited state are investigated by means of picosecond time-resolved fluorescence measurements. The fast internal conversion (IC) that has previously been observed for IDMAN, is also found for its 5- and 6-methoxy derivatives, while the IC rate decreases substantially in the 4- and 7-methoxy derivatives, showing that the fast IC is related to the proximity of the S-1 and S-2 states and also to the electronic structures of the S-1 and S-2 states. (c) 2005 Elsevier B.V. All rights reserved.
SELECTIVE LINEAR PEPTIDES WITH MELANOCORTIN-4 RECEPTOR (MC4-R) AGONIST ACTIVITY