An insight into the pharmacophores of phosphodiesterase-5 inhibitors from synthetic and crystal structural studies
摘要:
Selective inhibitors of cyclic nucleotide phosphodiesterase-5 (PDE5) have been used as drugs for treatment of male erectile dysfunction and pulmonary hypertension. An insight into the pharmacophores of PDE5 inhibitors is essential for development of second generation of PDE5 inhibitors, but has not been completely illustrated. Here we report the synthesis of a new class of the sildenafil derivatives and a crystal structure of the PDES catalytic domain in complex with 5-(2-ethoxy-5-(sulfamoyl)-3-thienyl)-1-methyl-3-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (12). Inhibitor 12 induces conformational change of the H-loop (residues 660-683), which is different from any of the known PDES structures. The pyrazolopyrimidinone groups of 12 and sildenafil are well superimposed, but their sulfonamide groups show a positional difference of as much as 1.5 angstrom. The structure-activity analysis suggests that a small hydrophobic pocket and the H-loop of PDE5 are important for the inhibitor affinity, in addition to two common elements for binding of almost all the PDE inhibitors: the stack against the phenylalanine and the hydrogen bond with the invariant glutamine. However, the PDE5-12 structure does not provide a full explanation to affinity changes of the inhibitors. Thus alternatives such as conformational change of the M-loop are open and further structural study is required. (C) 2008 Elsevier Inc. All rights reserved.
The present invention provides regulatable biocircuit systems. Such systems provide modular and tunable protein expression systems in support of the discovery and development of therapeutic modalities.
IDENTIFICATION AND TARGETED MODULATION OF GENE SIGNALING NETWORKS
申请人:CAMP4 THERAPEUTICS CORPORATION
公开号:US20210254056A1
公开(公告)日:2021-08-19
The present invention provides methods and compositions for the evaluation, alteration and/or optimization of gene signaling. Methods and systems are also provided which exploit the information generated in the identification of new targets and non-canonical signaling pathways.