The present work, spectroscopic and quantum computational study has been carried out for the molecule 4-oxo-4H-1-benzopyran-2-carboxylic acid. The stable conformer of the title molecule was identified using Potential Energy Surface (PES) scan. The structural and geometrical parameters of the stable conformer of the molecule were determined by Density Functional Theory (DFT) using B3LYP method along with the basis set 6-311++G(d,p) through Gaussian 09 W software. The theoretical and experimental investigations such as Vibrational (FT-IR and FT-Raman), UV–visible and NMR analysis were done. The FT-IR were recorded in the region of (4000–400 cm⁻¹) and FT-Raman in the region of (4000–100 cm⁻¹), and the vibrational bands were compared with the theoretical values. Carbon NMR and Proton NMR spectra have been analyzed in DMSO solution. The theoretical chemical shift values were determined using Gauge Independent Atomic Orbital (GIAO) method. The intermolecular and intra-molecular bonding of orbitals and transfer of charge were studied using the Natural Bond Orbital (NBO) analysis. The respective transitional study was done through UV–vis's spectra and theoretical values predicted using TD-DFT (Time Dependent – DFT) method for both gas and solvent (ethanol) state. HOMO (Highest Occupied Molecular Orbital) – LUMO (Lowest Unoccupied Molecular Orbital) energy gap results prove the exchange of charges inside the molecule. Molecular Electrostatic Potential (MEP) is used to identify the nucleophilic and electrophilic sites of the molecule. To check the bioactive nature of the title molecule the drug-likeness was determined. Molecular docking is used to analyze the biological activity of the title molecule. The distribution of torsional angles in a protein structure is viewed by the Ramachandran plots of the molecules.

目前的工作、光谱和量子计算研究已经针对分子 4-oxo-4H-1-苯并吡喃-2-羧酸进行。使用势能表面（PES）扫描鉴定了标题分子的稳定构象异构体。使用B3LYP方法以及基组6-311++G(d,p)通过Gaussian 09 W软件通过密度泛函理论(DFT)确定分子稳定构象异构体的结构和几何参数。进行了振动（FT-IR 和 FT-Raman）、紫外可见光和核磁共振分析等理论和实验研究。^{在(4000-400 cm -1} )区域记录FT-IR，在(4000-100 cm ^-1 )区域记录FT-Raman ，并将振动谱带与理论值进行比较。碳核磁共振和质子核磁共振谱已在 DMSO 溶液中进行了分析。使用规范独立原子轨道（GIAO）方法确定理论化学位移值。使用自然键轨道（NBO）分析研究了轨道的分子间和分子内键合以及电荷转移。相应的过渡研究是通过紫外可见光谱和使用 TD-DFT（时间相关 - DFT）方法对气体和溶剂（乙醇）状态预测的理论值完成的。HOMO（最高占据分子轨道）- LUMO（最低未占据分子轨道）能隙结果证明了分子内部的电荷交换。分子静电势 (MEP) 用于识别分子的亲核和亲电子位点。为了检查标题分子的生物活性性质，确定了药物相似性。分子对接用于分析标题分子的生物活性。蛋白质结构中扭转角的分布可以通过分子的拉马钱德兰图来观察。