3-Hydroxy-4-oxo-4H-pyrido[1,2-a]pyrimidine-2-carboxylates—A new class of HIV-1 integrase inhibitors

Aza-Povarov Reaction. A Method for the Synthesis of Fused Tetracyclic Chromeno[4,3-d]pyrido[1,2-a]pyrimidines

A cornerstone in drug discovery is the development of strategies to provide privileged small molecules with specific structural and stereochemical complexity, allowing access to new potential therapeutic entities. In this work, a new strategy based on the [4 + 2] Povarov reaction involving 1,3-diazadiene was developed. This approach is applied for a straightforward procedure in the preparation of chromeno[4,3-d]pyrido[1,2-a]pyrimidine derivatives, with accessible substrates, 2-aminopyridine and unsaturated aldehydes, and excellent atom economy to obtain four fused ring heterocycles, in a regio- and diastereoselective way.

Computational and Experimental Investigations of 7-(4-nitrophenyl)benzo[6,7]chromeno[3,2-e]pyrido[1,2-a]pyrimidin-6(7h)-one

Acstract:

In-silico studies are used for the prediction of the properties of several novel materials using computer simulation technique. The present study describes the complete description of the molecular vibrations and electronic feature of the title compound by this technique. 7-(4-nitrophenyl)benzo[6,7]chromeno[3,2-e]pyrido[1,2-a]pyrimidin-6(7H)-one was prepared by the multicomponent reaction of 2H-pyrido[1,2-a]pyrimidine-2,4(3H)-dione, 2-naphthol and p-nitrobenzaldehyde. The structure of the compound was confirmed by UV, IR, NMR (1H, 13C) and mass spectroscopic studies. The compound was further subjected to quantum chemical calculations at the level of Hartee-Fock (HF) method using Lan2DZ basis set to compute polarizability, hyperpolarizabilities, AIM approach, Natural bond orbital analysis, complete vibrational assignments, Mulliken charges, spectral analysis and HOMO-LUMO energies

KYNA Derivatives with Modified Skeleton; Hydroxyquinolines with Potential Neuroprotective Effect

Kynurenic acid (KYNA) is an endogenous neuroprotective agent of increasing importance. Several derivatives have already been synthesized, bearing an abundance of functional groups attached to the main skeleton in different positions. Several of these compounds have already been tested in biological evaluations, with several of them targeting the same receptors and biological effects as KYNA. However, these modified compounds build upon the unmodified KYNA skeleton leaving a possible route for the synthesis of new, potentially neuroprotective derivatives with heteroatom-containing ring systems. The aim of this review is to summarize the syntheses of KYNA derivatives with altered skeletons and to pinpoint an appealing transformation for future medicinal lead molecules.

Design, Synthesis, Molecular Modeling Study and Biological Evaluation of New N'-Arylidene-pyrido [2,3-d]pyrimidine-5-carbohydrazide Derivatives as Anti-HIV-1 Agents

In an attempt to identify potential new agents that are active against HIV-1, a series of novel pyridopyrimidine-5-carbohydrazide derivatives featuring a substituted benzylidene fragment were designed and synthesized based on the general pharmacophore of HIV-1 integrase inhibitors. The cytotoxicity profiles of these compounds showed no significant toxicity to human cells and they exhibited anti-HIV-1 activity with EC50 values ranging from 90 to 155 µM. Compound 5j bearing 4-methylbenzylidene group was found to be the most active compound with EC50 = 90 µM and selectivity index, CC50/EC50 = 6.4. Molecular modeling studies indicated the capacity of compound 5j to interact with two Mg2+ cations and several residues that are important in HIV-1 integrase inhibition. These findings suggested that pyridopyrimidine-5-carbohydrazide scaffold might become a promising template for development of novel anti-HIV-1 agents.

Structure–activity relationship and binding mode studies for a series of diketo-acids as HIV integrase inhibitors by 3D-QSAR, molecular docking and molecular dynamics simulations

We explored the main factors affecting the activity of compounds by different statistical and computational methods.

Sketching the historical development of pyrimidones as the inhibitors of the HIV integrase

Heterocyclic substances perform a very unique role in drug design and discovery. This article provides the primary objectives of the analysis within pyrimidine centered new heterocyclic elements chronologically from their finding focusing on one of the essential enzyme of HIV virus particle that is integrase upon suppressing its strand transfer function. The class of compounds reviewed here includes bicyclic pyrimidines, dihydroxypyrimidines, pyrimidine-2,4-dinones, N-methylpyrimidones, pyranopyrimidine, pyridine-quinoline conjugates, pyrimidine-2-carboxamides, N-3 hydroxylated pyrimidine-2,4-diones as well as their various substituted analogues. Such initiatives released an effective drug Raltegravir as a first FDA approved anti-HIV integrase inhibitor as well as several of its derivatives along with other pyrimidones is under clinical or preclinical growth. Some of the provided scaffolds indicated dual anti-HIV efficacies against HIV reverse transcriptase and integrase enzymes at both cites as 3'-processing and strand transfer, while several scaffolds exhibited potency against Raltegravir resistant HIV mutant strains determining themselves a potent class of compounds having appealing upcoming implementations. Connections of the new compounds' molecular structure and HIV viral target has been overviewed to be able to accomplish further growth of promising anti-HIV agents in future drug discovery process.

Synthesis of highly substituted 4H-pyrido[1,2-a]pyrimidines via a one-pot three-component condensation reaction

A one-pot three-component reaction, involving condensation of 2-aminopyridines, aldehydes, and ketones/aldehydes under trifluoromethanesulfonic acid catalysis, provides rapid access to highly substituted novel 4H-pyrido[1,2-a]pyrimidines.

Pharmacophore development and docking studies of the hiv-1 integrase inhibitors derived from N-methylpyrimidones, Dihydroxypyrimidines, and bicyclic pyrimidinones

To elucidate the crucial structural features for the HIV-1 integrase inhibitors, a three-dimensional pharmacophore model was developed based on N-methyl pyrimidones, dihydroxypyrimidines, and bicyclic pyrimidinones derivatives using Phase. N-methyl pyrimidone derivative raltegravir, the first US-FDA approved drug by Merck, belongs to this series. The best-fitted common pharmacophore hypothesis was characterized by two acceptor, two hydrophobic, and two ring features having a correlation coefficient of 0.895, cross-validated Q(2) value of 0.631, and survival score of 8.862, suggesting that a highly predictive pharmacophore model was developed. The cross-validation studies using 23 test set molecules and fifteen structurally diverse HIV-integrase inhibitors give extra confidence about the correctness of the pharmacophore model. The cross-validation studies proved that our developed model can successfully differentiate between active and inactive HIV-integrase inhibitors. The docking studies were also carried out wherein the molecules were docked against the active site of HIV integrase to analyze the binding mode and the necessary structural requirement for their respective enzymatic inhibition. The results obtained from our studies provide a valuable tool for designing of new lead molecules with potent activity.