Synthesis and anticancer activity of (RS)-9-(2,3-dihydro-1,4-benzoxaheteroin-2-ylmethyl)-9H-purines

Recent Developments and Future Perspectives of Purine Derivatives as a Promising Scaffold in Drug Discovery

Numerous purine-containing compounds have undergone extensive investigation for their medical efficacy across various diseases. The swift progress in purine-based medicinal chemistry has brought to light the therapeutic capabilities of purine-derived compounds in addressing challenging medical conditions. Defined by a heterocyclic ring comprising a pyrimidine ring linked with an imidazole ring, purine exhibits a diverse array of therapeutic attributes. This review systematically addresses the multifaceted potential of purine derivatives in combating various diseases, including their roles as anticancer agents, antiviral compounds (anti-herpes, anti-HIV, and anti-influenzae), autoimmune and anti-inflammatory agents, antihyperuricemic and anti-gout solutions, antimicrobial agents, antitubercular compounds, anti-leishmanial agents, and anticonvulsants. Emphasis is placed on the remarkable progress made in developing purine-based compounds, elucidating their significant target sites. The article provides a comprehensive exploration of developments in both natural and synthetic purines, offering insights into their role in managing a diverse range of illnesses. Additionally, the discussion delves into the structure-activity relationships and biological activities of the most promising purine molecules. The intriguing capabilities revealed by these purine-based scaffolds unequivocally position them at the forefront of drug candidate development. As such, this review holds potential significance for researchers actively involved in synthesizing purine-based drug candidates, providing a roadmap for the continued advancement of this promising field.

A comprehensive computational approach for the identification of structure-based potential pharmacological candidates as selective AKR1B1 and AKR1B10 inhibitors: repurposing of purine alkaloids for the treatment of cancer

Significant metabolic pathways have been linked to AKR1B1 and AKR1B10. These enzymes are crucial biological targets in the therapy of colon cancer. In the past several decades, drug repurposing has gained appeal as a time and cost-efficient strategy for providing new indications for existing drugs. The structural properties of the plant-based alkaloidal drugs theobromine and theophylline were examined using density functional theory (DFT) computations, where the B3LYP/SVP method was used to quantify the dipole moment, polarizability, and optimization energy. Optimized structures obtained through DFT studies were docked inside the active pocket of target proteins to evaluate their inhibitory potential. Moreover, molecular dynamic simulation provides significant insight into a dynamic view of molecular interactions. The findings of current revealed theobromine and theophylline as strong AKR1B1 and AKR1B10 inhibitors, respectively. In addition, the anti-cancer potential of theophylline and theobromine was validated by targeting various tumor proteins, i.e. NF-κB, cellular tumor antigen P53 and caspase-3 using a molecular docking approach. Theobromine was found to be strongly interacted with NF-κB and caspase-3, whereas theophylline potentially inhibited cellular tumor antigen P53. In addition, the ADMET characteristics of theobromine and theophylline were identified, confirming their drug-like capabilities. These results should open the way for further experimental validation and structure-based drug design/repurposing of AKR1B1/AKR1B10 inhibitors for the treatment of colon cancer and associated malignancies.Communicated by Ramaswamy H. Sarma.

Synthesis and Cytotoxic Activity of the Derivatives of N-(Purin-6-yl)aminopolymethylene Carboxylic Acids and Related Compounds

Testing a number of N-[omega-(purin-6-yl)aminoalkanoyl] derivatives of 7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine in a panel of nine tumor cell lines has shown that the studied compounds exhibit high cytotoxic activity, especially against 4T1 murine mammary carcinoma, COLO201 human colorectal adenocarcinoma, SNU-1 human gastric carcinoma, and HepG2 human hepatocellular carcinoma cells. Synthesis and study of structural analogs of these compounds made it possible to find that the presence of both a difluorobenzoxazine fragment and a purine residue bound via a linker of a certain length is crucial for the manifestation of the cytotoxic activity of this group of compounds. The study of the effect of the most promising compound on the cell cycle of the human tumor cell lines, the most sensitive and least sensitive to cytotoxic action (MDA-MB-231 breast adenocarcinoma and COLO201 colorectal adenocarcinoma, respectively), allows us to conclude that this compound is an inhibitor of DNA biosynthesis. The found group of purine conjugates may be of interest in the design of new antitumor agents.

Heterocyclic Compounds as Hsp90 Inhibitors: A Perspective on Anticancer Applications

Heat shock proteins (Hsps) have garnered special attention in cancer therapy as molecular chaperones with regulatory/mediatory effects on folding, maintenance/stability, maturation, and conformation of proteins as well as their effects on prevention of protein aggregation. Hsp90 ensures the stability of various client proteins needed for the growth of cells or the survival of tumor cells; therefore, they are overexpressed in tumor cells and play key roles in carcinogenesis. Accordingly, Hsp90 inhibitors are recognized as attractive therapeutic agents for investigations pertaining to tumor suppression. Natural Hsp90 inhibitors comprising geldanamycin (GM), reclaimed analogs of GM including 17-AAG and DMAG, and radicicol, a natural macrocyclic antifungal, are among the first potent Hsp90 inhibitors. Herein, recently synthesized heterocyclic compounds recognized as potent Hsp90 inhibitors are reviewed along with the anticancer effects of heterocyclic compounds, comprising purine, pyrazole, triazine, quinolines, coumarin, and isoxazoles molecules.

Pyrimidine: a review on anticancer activity with key emphasis on SAR

Background

Cancer is a global health challenge, it impacts the quality of life and its treatment is associated with several side effects. Resistance of the cancer cells to the existing drugs has led to search for novel anticancer agents. Pyrimidine, a privileged scaffold, is part of living organisms and plays vital role in various biological procedures as well as in cancer pathogenesis. Due to resemblance in structure with the nucleotide base pair of DNA and RNA, it is recognized as valuable compound in the treatment of cancer.

Main text

Many novel pyrimidine derivatives have been designed and developed for their anticancer activity in the last few years. The present review aims to focus on the structure activity relationship (SAR) of pyrimidine derivatives as anticancer agent from the last decade.

Conclusion

This review intends to assist in the development of more potent and efficacious anticancer drugs with pyrimidine scaffold.

Graphical abstract

Theoretical calculations of molecular descriptors for anticancer activities of 1, 2, 3-triazole-pyrimidine derivatives against gastric cancer cell line (MGC-803): DFT, QSAR and docking approaches

This work used quantum chemical method via DFT to calculate molecular descriptors for the development of QSAR model to predict bioactivity (IC50- 50% inhibition concentration) of the selected 1, 2, 3-triazole-pyrimidine derivatives against receptor (human gastric cancer cell line, MGC-803). The selected molecular parameters were obtained by B3LYP/6-31G∗∗. QSAR model linked the molecular parameters of the studied compounds to their cytotoxicity and reproduced their observed bioactivities against MGC-803. The calculated IC50 tailored the observed IC50 and greater than standard compound, 5-fluorouracil, suggesting that the developed QSAR model reproduced the observed bioactivity. Statistical analyses (including R2, CV. R2 andR a 2 gave 0.950, 0.970 and 0.844 respectively) revealed a very good fitness. Molecular docking studies revealed the hydrogen bonding with the amino acid residues in the binding site, as well as ligand conformations which are essential feature for ligand-receptor interactions. Therefore, the methods used in this study are veritable tools that can be employed in pharmacological and medicinal chemistry researches in designing better drugs with improve potency.

Purine derivatives with heterocyclic moieties and related analogs as new antitumor agents

AIM

Identification of new antiproliferative compounds.

METHODOLOGY

Four series of compounds were synthesized by the Mitsunobu reaction. Their antiproliferative activity was studied against several cancer cells and a noncancerous fibroblast cell line. Their apoptotic activity was analyzed using a caspase 3/7 fluorescence assay.

RESULTS & CONCLUSION

9-alkylated-6-halogenated and 2,6-dihalogenated purines show remarkable inhibition of tumor cell proliferation, with the dichloro derivatives being the most potent of all the series. The most promising compound, tetrahydroquinoline 4c, exhibits significant antiproliferative activity against the cancer cells tested, while displaying a 19-fold lower potency against noncancerous fibroblasts, a key feature that indicates potential selectivity against cancer cells. This compound produces a high percentage of apoptosis (58%) after 24 h treatment in human breast cancer MCF-7 cells.

Density functional theory calculations, vibration spectral analysis and molecular docking of the antimicrobial agent 6-(1,3-benzodioxol-5-ylmethyl)-5-ethyl-2-{[2-(morpholin-4-yl)ethyl] sulfanyl}pyrimidin-4(3H)-one

Vibrational spectral analysis and quantum chemical computations based on density functional theory have been performed on the antimicrobial agent 6-(1,3-benzodioxol-5-ylmethyl)-5-ethyl-2-{[2-(morpholin- 4-yl)ethyl]sulfanyl}pyrimidin-4-(3H)-one.The equilibrium structural geometry, various bonding features and harmonic vibrational wavenumbers of the title compound have been investigated using DFT-B3LYP function at 6-311++G(d, p) basis set. The detailed interpretations of the vibrational spectra have been carried out with the aid of VEDA 4 program. The various intramolecular interactions of the title compound have been exposed by natural bond orbital analysis. The FT-IR and FT-Raman spectra of the title molecule have been recorded and analyzed. Blue-shifting of the C-H wavenumber along with a decrease in the C-H bond length attribute for the formation of the C-H...O hydrogrn bonding provide an evidence for a charge transfer interaction. Also, the distribution of natural atomic charges reflects the presence of intramolecular hydrogen bonding. The analysis of the electron density of HOMO and LUMO gives an idea of the delocalization and the low value of energy gap indicates electron transfer within the molecule. Moreover, molecular docking studies revealed the possible binding of the title molecule to different antimicrobial target proteins.

Discovery of 6-chloro-2-(propylthio)-8,9-dihydro-7H-purines containing a carboxamide moiety as potential selective anti-lung cancer agents

A new series of 6-chloro-2-(propylthio)-8,9-dihydro-7H-purine-8-caboxamide derivatives were designed, synthesized, and further evaluated for their antiproliferative activities on four human cancer cell lines (A549, MGC803, PC-3 and TE-1). The structure-activity relationships (SARs) studies were conducted through the variation in the two regions, which including position 8 and 9, of purine core. One of the compounds, 8, containing a terminal piperazine appendage with a carboxamide moiety at position 8 and phenyl group at position 9 of 6-chloro-8,9-dihydro-7H-purine core, showed the most potent antiproliferative activity and good selectivity between cancer and normal cells (IC₅₀ values of 2.80 μM against A549 and 303.03 μM against GES-1, respectively). In addition, compound 8 could inhibit the colony formation and migration of A549 cells in a concentration-dependent manner, as well as induce the apoptosis possibly through the intrinsic pathway.

Design strategies, structure activity relationship and mechanistic insights for purines as kinase inhibitors

Kinases control a diverse set of cellular processes comprising of reversible phosphorylation of proteins. Protein kinases play a pivotal role in human tumor cell proliferation, migration and survival of neoplasia. In the recent past, purine based molecules have emerged as significantly potent kinase inhibitors. In view of their promising potential for the inhibition of kinases, this review article focuses on purines which have progressed as kinase inhibitors during the last five years. A detailed account of the design strategies employed for the synthesis of purine analogs exerting inhibitory effects on diverse kinases has been presented. Apart from presenting the design strategies, the article also highlights the structure activity relationship along with mechanistic insights revealed during the biological evaluation of the purine analogs for kinase inhibition. The interactions with the amino acid residues responsible for kinase inhibitory potential of purine based molecules have also been discussed. In this assemblage, purine based protein kinase inhibitors patented in the past have also been summarized in the tabular form. This compilation will be of great interest for the researchers working in the area of protein kinase inhibitors.

p-Nitrobenzenesulfonamides and their fluorescent dansylsulfonamides derived from N-alkylated o-(purine-methyl)anilines as novel antitumour agents

10 shows an IC₅₀ = 134 nM (A-375). Its dansyl analogue is absorbed (P.O.) accumulating mainly in liver and kidney.

Synthesis and anticonvulsant activity of novel purine derivatives

A series of new purines containing triazole and other heterocycle substituents was synthesized and evaluated for their preliminary anticonvulsant activity and neurotoxicity by using the maximal electroshock (MES), subcutaneous pentylenetetrazole (scPTZ) and rotarod neurotoxicity (TOX) tests. Among the compounds studied, 9-decyl-6-(1H-1,2,4-triazol-1-yl)-9H-purine (5e) was the most potent compound, with a median effective dose of 23.4 mg/kg and a high protective index of more than 25.6 after intraperitoneal administration in mice. Compound 5e showed significant oral activity against MES-induced seizures in mice, with an ED50 of 39.4 mg/kg and a PI above 31.6. These results demonstrate that compound 5e possesses better anticonvulsant activity and is safer than the commercially available drugs carbamazepine and valproate in MES, scPTZ and TOX models.

Stereospecific alkylation of substituted adenines by the Mitsunobu coupling reaction under microwave-assisted conditions

The Mitsunobu reaction under microwave-assisted conditions reveals a complete inversion of the stereogenic centre of the secondary alcohol giving an alkylated purine linked to a homochiral six-membered ring.

Subtle Mitsunobu couplings under super-heating: the role of high-throughput continuous flow and microwave strategies

Fragile Mitsunobu reaction can efficiently be performed under super-heating.

Synthesis and evaluation as antitumor agents of 1,4-naphthohydroquinone derivatives conjugated with amino acids and purines

We report on the synthesis of two series of 1,4-naphthohydroquinone derivatives conjugated with amino acids (Gly, Ala, Phe, and Glu) and with substituted purines linked by an aliphatic chain. The compounds were obtained through Diels-Alder cycloaddition between myrcene and 1,4-benzoquinone and evaluated in vitro for their cytotoxicity (GI50 ) against cultured human cancer cells of A-549 lung carcinoma, HT-29 colon adenocarcinoma, and MCF-7 breast carcinoma. The GI50 values found for some hydroquinone-amino acid and hydroquinone-purine hybrids against MCF-7 are in an activity range comparable to that of the reference drug doxorubicin.