In the present study, the structural and spectroscopic investigations of Methyl 6-Aminopyridine-3-carboxylate (MAPC) molecule were performed using density functional theory (DFT) quantum chemical calculations. Molecular docking analysis was used to find out the inhibitory nature of the title molecule. The most stable molecular structure was predicted using conformational analysis at DFT/B3LYP level of cc-pVTZ basis set. The optimization was carried out using DFT/B3LYP method with cc-pVTZ basis to find out the most stable molecular structure of the molecule. The optimized molecular structure was used to determine the vibrational frequencies, which were assigned and compared with the experimentally observed vibrational frequencies. The Gauge-Invariant-atomic orbital (GIAO) method was used to calculate the ¹³C NMR isotropic chemical shift values of the molecule in DMSO solution and compared with experimental data. The ultraviolet-visible spectra of the molecule were used to find out the electronic properties of the molecule and are confirmed experimentally. The HOMO-LUMO energies, energy gap, chemical potential (μ) electronegativity (χ), hardness (η) and softness (S) values were calculated which results in the stability and molecular reactivity of the molecule. The second order perturbation energy E(2) values of the molecule were calculated using natural bond orbital analysis, which indicates the bioactivity of the molecule. Mullikan atomic charge distribution was calculated. Molecular Electrostatic potential (MEP) surface was computed and visualized by GaussView 05. The obtained lower binding energy and intermolecular energy values of MAPC ligand docked with HLA-DRB1 protein compared to the other selected proteins confirms that the title molecule can be useful for treatment of sarcoidosis disease. Hence, the present study paves the way for the development of novel drugs associated with sarcoidosis disease.

在本研究中，使用密度泛函理论（DFT）量子化学计算进行了6-氨基吡啶-3-羧酸甲酯（MAPC）分子的结构和光谱研究。使用分子对接分析来发现标题分子的抑制性质。使用构象分析在cc-pVTZ基集的DFT / B3LYP水平上预测了最稳定的分子结构。使用cc-pVTZ为基础的DFT / B3LYP方法进行了优化，以找出分子中最稳定的分子结构。优化的分子结构用于确定振动频率，将其分配并与实验观察到的振动频率进行比较。量规不变原子轨道（GIAO）方法用于计算¹³分子在DMSO溶液中的C NMR各向同性化学位移值，并与实验数据进行比较。该分子的紫外-可见光谱被用于发现该分子的电子性质并通过实验得到证实。计算出HOMO-LUMO能量，能隙，化学势（μ），电负性（χ），硬度（η）和柔软度（S）值，这些值可导致分子的稳定性和分子反应性。使用自然键轨道分析计算分子的二级扰动能量E（2）值，这表明分子的生物活性。计算了Mullikan原子电荷分布。分子静电势（MEP）表面通过GaussView 05计算并可视化。与其他选定的蛋白质相比，与HLA-DRB1蛋白质对接的MAPC配体获得的较低的结合能和分子间能值证实了该标题分子可用于治疗结节病。因此，本研究为结节病相关药物的开发铺平了道路。