In silico ADME/Pharmacokinetic and Target Prediction Studies of Ethambutol as Drug Molecule

Background: The conventional approach for the development of any pharmaceutically active molecule is a time-consuming and costly process because the synthesis is followed by laboratory tests which are then followed by long clinical trials. Hence a faster approach is desired. This article discusses Ethambutol, a frontline anti-tubercular drug that has its properties predicted by the SwissADME tool and the results would be compared with the findings published in the literature. Objective: The main objective is to study the predicted and experimental ADME properties, compare them. As well as study the predicted targets and understand the use of SwissADME for designing other drug molecules. Method: SwissADME, an online tool for ADME prediction was used along with Swiss Target Prediction to understand the targets of the drug. Further, experimental data was obtained from the available scientific literature. Results: We found certain similarities between the predicted and experimental data. However, there were some variations, depending on the testing conditions. The results are interpreted ahead in the article. Conclusion: Ethambutol’s predicted ADME properties are discussed and as per findings from results, it can be concluded that other drug molecules can be similarly predicted using these tools. Also, based on predicted data we can reformulate and prepare some different preparations of the drug.

Application of LFER to pKas and Dipole Moments of 1H and 2H Tautomers of Tetrazole: Mimicking Structure-Function Relation as a Chemical Education Perspective

Structure-function relation is a 155 year old concept to explain the dependence of biological activity of a drug molecule on its structure put forward by Crum-Brown and Fraser*. Similar line of interest is followed in the present work, and it stimulates the understanding of structure-activity relation (SAR) among the graduate students. An attempt is made for the first time from our laboratory to apply the Hammett and Taft equations to a five membered ring system with four nitrogens as heteroatoms viz. tetrazole to identify the aqueous medium 1H and 2H Tautomers. For this purpose experimentally determined aqueous medium pKa values of NH-acidities of a total of fifteen 5-X-1,2,3,4-tetrazoles and DFT/B3LYP method at the 6-31G* level calculated dipole moments of seven 1H and 2H tautomers of 5-X-1,2,3,4-tetrazoles are used to correlate with Hammett para and meta, and Taft _ortho^* values. Good correlations are obtained. The promising response of more abundant and more polar 1H tautomer with less susceptibility (* = -1.38 in pKa correlations and * = -0.55 in dipole moments correlation) to Taft equation and less abundant and less polar 2H tautomer with more susceptibility (para = 6.56, meta = 7.79 in pKa correlations, and para = 2.69, meta = 3.26 in dipole moments correlation) to Hammett equation of the tetrazole is well distinguished. Thus it mimics a principle of structure-function study on a chemical property like the ionization of NH proton of tetrazole and on a physical property like dipole moment for the first time. Therefore finding a way is achieved to get the equilibrium identification of 1H and 2H tautomers without using any expensive and time consuming experimental techniques.

Formulation and evaluation of oral disintegrating tablets of furosemide

Orally disintegrating tablets of Furosemide were prepared, evaluated and the comparison of the action of different concentrations of disintegrants on disintegration and dissolution of the tablets were studied. Direct compression method was used to prepare the orally disintegrating tablets containing 20 mg of Furosemide. The formulation was conducted using different concentrations of crospovidone, croscarmellose and sodium starch glycolate as superdisintegrants and their interactions with Furosemide were also evaluated using FTIR. FTIR studies using the drug and its mixtures with the excipients showed that the peaks correlate with one another which signify that there is no interaction between the drug molecule and the excipients used. The obtained results revealed that the disintegration time of ODTs were between 9 to 59 seconds. The percentage drug content of tablets in all the formulations was found between 91.51% to 106.69%, which complies with the limits established in pharmacopoeia. The in-vitro dissolution studies show maximum release of 89.47% in formulation F3 and minimum of 77.64% in formulation F12. Higher concentration of crospovidone and croscarmellose in formulations F3 and F6 showed better dissolution properties than SSG. So by varying the concentrations of superdisintegrants, oral disintegrating tablets can be formulated.

Formulation development and evaluation of Orally Disintegrating Tablets Rizatriptan Benzoate

Formulation research is oriented towards safety, efficacy and quick onset of action of existing drug molecule through novel concepts of drug delivery. Orally disintegrating tablets of Rizatriptan benzoate were prepared by direct compression method to provide faster relief from pain to migraine sufferers. About eleven formulations for the present study were carried out. Croscarmellose sodium, Crospovidone and Sodium starch glycolate (SSG) were used as superdisintegrants, while microcrystalline cellulose was used as diluent. The prepared batches of tablets were evaluated for weight variation, hardness, friability, wetting time, invitro dispersion time, drug content and invitro dissolution studies. The formulation containing combination of Croscarmellose sodium and Sodium starch glycolate showed rapid invitro dispersion time as compared to other formulations. The optimized formulation dispersed in 8 seconds. It also showed a higher water absorption ratio and 99.58% of drug is released within 2 minutes.

In-Silico Analysis to Identify Potent Quinoline Analogues Against Multi-Targets of SARS-CoV-2

In the current outbreak of COVID-19, various studies have been conducted all over the world to develop effective drugs against the virus. Recent studies have shown that hydroxychloroquine, chloroquine (antimalarial drugs), isoflavones, flavonoids, etc. have potent antiviral properties, and few have been proven as effective drugs for the preventive treatment of COVID-19. But their exact action against SARS-CoV-2 is still unknown. The strategy of this study is the virtual screening of quinoline analogues, design new ligand molecules, perform molecular interaction analysis, their MD validation against multi targets (Spike-ACE2, TMPRSS2, and Spike Protein) of SARS-CoV-2, and to suggest the most promising and effective drug molecule. Hydroxychloroquine and chloroquine were considered as the reference molecules in this study. A ligand N-[4-(3-Benzylideneazetidine-1-carbonyl)phenyl]quinoline-8-sulfonamide interacting with TMPRSS2 shows better interaction among the list even after MD validation. Further in-vitro and in-vivo analysis of this study is needed for future validation.

Chemotherapeutic Applications of Folate Prodrugs: A Review

Several techniques to assisting in the drug design and discovery stages have been developed during the last several decades. The bulk of these techniques aimed to find novel chemical entities that had the greatest significant interaction with the targeted receptors or enzymes while providing the least degree of risk of unwanted interactions. This approach, on the other hand, is time-consuming and expensive, as it requires the screening of thousands of molecules for biological activity, with only one making it to market. The prodrug strategy, in which the active drug molecule is disguised by a promoiety to change its undesirable characteristics, is one of the most appealing and promising methods. The folate receptor (FR)-targeted systems may also open the path for more advanced drug conjugates, especially because this receptor is now being targeted by a variety of technological innovations, including nanoparticles, small molecules, and protein-based technologies, resulting in a wealth of experience in the discipline.

REVIEW ON THE SYNTHESIS AND POTENTIAL THERAPEUTIC APPLICATIONS OF HETEROCYCLIC PRODUCTS OF 5-AMINO-3-METHYLISOXAZOLE

In general, heterocyclic compounds have evoked interest and concern because of their fundamental role in biological profiles and biological actions in nature. Now, most of the lead molecules in medicinal chemistry are based on hetero-atoms. In medicinal chemistry- to bring two hetero-atoms to the drug molecule, isoxazoles are interesting functional groups. Isoxazole as a key building block has been widely used and is an important heterocyclic unit.