It is worthy to mention here that the compound library consists of structural features derived from five different classes which cover overlapping features and thereafter holds good chances of identification of pharmacophoric BYL719 chemical structure requirements. After retrieving sequence of alpha-1 (α1)-adrenergic receptor from uniprot (P35348), BLAST15 has resulted in 36% identity and core conserved similarity 71 % with similar template of chain A beta2 adreno receptor (PDB ID 2R4R_A)

having sequence length of 365 in Homo sapiens from Protein Database Bank (PDB). 16 Protein modeling has been performed using Deep View/Swiss PDB Viewer and Swiss Model server. 17 The primary polypeptide chain of alpha-1 (α1)-adrenergic receptor was aligned on the backbone of template (chain A beta2 adreno receptor, PDB ID 2R4R_A) which

then was followed by side chain optimization using the simultaneous global optimization of the energy for all non-identical residues. Structural validation of the modeled 3D alpha-1 (α1)-adrenergic receptor was assessed using most popular structure validation find more tool Procheck 18 and Ramchandranplot. 19 Molecular docking program Molegro Virtual Docker (MVD) based on PLP score and PLANTS Score provided a flexible platform for docking of the compound library of all 1000 candidates. The PLP scoring functions was first reported by Gehlhaar et al20 and 21 and its advanced form was introduced by Yang and Chen22 Similarly PLANTS scoring function was recently incorporated in MVD developed and reported by Korb et al.23 GRID resolution was set to 0.30 A0. Antagonists were evaluated on the basis of the internal ES (Internal electrostatic Interaction), internal hydrogen bond interactions and sp2–sp2 torsions. With reference to

literature reported and discussed above,10 the center of binding site was set on the coordinates values X = 11.49, Y = 57.28, and Z = 43.36. Default parameters were used including maximum iteration of 1500 and a maximum population Rolziracetam size of 50. The 3D structure of alpha-1A-adrenergic receptor model (Fig. 1a) qualified all the structure protein quality parameters. Results of homology modeling of alpha-1A-adrenergic receptor and its structure validation using Ramachandran plot confirm the structural quality by allocating only 0.6% of total residues in disallowed region. The remaining 71.4 % of the amino acids are found in the core region, 25.1 % of them are distributed in the allowed region, while 2.9% are found in the generously allowed region (Fig. 1b). The energy minimization tool for modeled structures calculated that thermodynamical free energy of the modeled structure to −835.042 KJ/mol. Newly modeled 3D Structure of alpha-1A-adrenergic receptor was chosen for carrying out docking studies.