Synthesis, Characterization, and Anticancer Activity of Benzothiazole Aniline Derivatives and Their Platinum (II) Complexes as New Chemotherapy Agents

We describe the synthesis, characterization, molecular modeling, and in vitro anticancer activity of three benzothiazole aniline (BTA) ligands and their corresponding platinum (II) complexes. We designed the compounds based on the selective antitumor properties of BTA, along with three types of metallic centers, aiming to take advantage of the distinctive and synergistic activity of the complexes to develop anticancer agents. The compounds were characterized using nuclear magnetic resonance spectrometry, Fourier transform infrared spectroscopy, mass spectrometry, elemental analysis, and tested for antiproliferative activity against multiple normal and cancerous cell lines. L1, L2, and L1Pt had better cytotoxicity in the liver, breast, lung, prostate, kidney, and brain cells than clinically used cisplatin. Especially, L1 and L1Pt demonstrated selective inhibitory activities against liver cancer cells. Therefore, these compounds can be a promising alternative to the present chemotherapy drugs.

Liquid chromatographic enantioseparation, determination, bioassay and isolation of enantiomers of Ketorolac: A review

Ketorolac (Ket) is a potent non-narcotic analgesic drug (among the nonsteroidal anti-inflammatory drugs). The physiological activity of Ket resides with (S)-(−)-Ket while the drug is marketed and administered as a racemic mixture. Therefore, it is desirable that the pharmacokinetics is measured and quantified for enantiomers individually and not as a total drug. The present paper is focused on relevant literature on LC enantioseparation of (RS)-Ket along with bioassay, pharmacokinetic and clinical studies within the discipline of analytical chemistry. HPLC and Thin layer chromatography (TLC) methods using both direct and indirect approaches are discussed. The methods provide chirality recognition even in the absence of pure enantiomers. Besides, a brief discussion on resolution by crystallization and enzymatic methods is included. The most interesting aspects include establishment of structure and molecular asymmetry of diastereomeric derivatives using LC-MS, proton nuclear magnetic resonance spectrometry, and by drawing conformations in three dimensional views by using certain software. A brief discussion has also been provided on the recovery of native enantiomers by TLC.

Integrating genomics and metabolomics for scalable non-ribosomal peptide discovery

Non-Ribosomal Peptides (NRPs) represent a biomedically important class of natural products that include a multitude of antibiotics and other clinically used drugs. NRPs are not directly encoded in the genome but are instead produced by metabolic pathways encoded by biosynthetic gene clusters (BGCs). Since the existing genome mining tools predict many putative NRPs synthesized by a given BGC, it remains unclear which of these putative NRPs are correct and how to identify post-assembly modifications of amino acids in these NRPs in a blind mode, without knowing which modifications exist in the sample. To address this challenge, here we report NRPminer, a modification-tolerant tool for NRP discovery from large (meta)genomic and mass spectrometry datasets. We show that NRPminer is able to identify many NRPs from different environments, including four previously unreported NRP families from soil-associated microbes and NRPs from human microbiota. Furthermore, in this work we demonstrate the anti-parasitic activities and the structure of two of these NRP families using direct bioactivity screening and nuclear magnetic resonance spectrometry, illustrating the power of NRPminer for discovering bioactive NRPs.

A Potentially Useful Procedure for Conversion of Ethers to Esters

This communication reports a catalytic system for transformation of ethers into their corresponding esters, especially for cyclic ethers. This efficient procedure was developed as part of our efforts to synthesize nucleoside building blocks and their derivatives. Gas Chromatography-Mass Spectrometry (GC-MS) monitored the reaction processes, Nuclear Magnetic Resonance Spectrometry (NMR), and Infrared Spectrometry (IR) were used to verify the structure of the products. The conversions of Tetrahydrofuran (THF) and other cyclic ether into lactones were accomplished in high yield, over 95%. This approach could be extended too many types of ethers to produce directly corresponding esters simply. Four representatives of ethers were investigated. Cyclic ethers have the higher yields. Linear ethers gave lower yields. The reaction on methoxylcarbon or methyl ether carbon was not observed. The reacted catalyst can be reused over several times. For each reusing, only drops of sulfuric acid need to be added. Nevertheless, the asymmetric ethers selectivity needs to be addressed in future studies.

Reaction mechanisms of alkali-activated materials

abstract: The Alkali-Activated Materials (AAM) are defined as materials obtained through the reaction between precursors and activators, and are separated into two classes depending on the products formed in the reaction, those rich in calcium, as the blast furnace slag, whose Ca/(Si+Al) ratio is higher than 1; and poor in calcium, which is the geopolymers subclass. In this review article, some bibliographical aspects were discussed regarding the discovery of these materials, through research conducted by Victor Glukhovsky and through the characterization of historical monuments by Davidovits, which began in the 50s and 60s and persist to the present day. The main products obtained in the alkaline activation reaction were also addressed, using the definition of polysialates and zeolites, in the case of geopolymers, and the tobermorite structure, in the case of materials rich in calcium. The main steps of the alkali-activated reaction, such as dissolution, condensation, polycondensation, crystallization, and hardening, were discussed. Some techniques for characterizing the AA reaction products were also examined, such as X-ray diffraction (XRD), nuclear magnetic resonance spectrometry (NMR), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Finally, the main factors that interfere in the kinetics of AA reactions were explored, in which the type of cure and the activating solution used in the alkali-activated materials production stands out.

ANTIFUNGAL AND ANTIBIOFILM ACTIVITY OF 2-BROMO-N-PHENYLCETAMIDE AGAINST CRYPTOCOCCUS NEOFORMANS

Objective: This study aimed to evaluate the antifungal and antibiofilm of 2-bromo-N-phenylacetamide (A1Br) against Cryptococcus neoformans in vitro. Methods: The compound was characterized by infrared and 1H-nuclear magnetic resonance spectrometry data. Minimum inhibitory concentration (MIC) was determined using the plate dilution method and biofilm formation inhibition of the crystal violet assay. Results: A1Br inhibited the growth of C. neoformans with MIC of 0.25 and 0.5 μg/ml and has good antibiofilm activity MIC ×4, with ≥80% inhibition growth. Conclusions: Thus, A1Br shows potential antifungal and antibiofilm agents for the treatment of infections caused by C. neoformans, as well as the eradication of cryptococcal colonization of medical prosthetic devices.