A5082819002- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Marine Sponges and Natural Products
- Chemical Synthesis and Analysis
- Traditional and Medicinal Uses of Annonaceae
- Microbial Natural Products and Biosynthesis
- Cancer therapeutics and mechanisms
- Synthetic Organic Chemistry Methods
- Phenothiazines and Benzothiazines Synthesis and Activities
- Chemical synthesis and alkaloids
- Antifungal resistance and susceptibility
- Alkaloids: synthesis and pharmacology
- Synthesis and Biological Evaluation
- Asymmetric Synthesis and Catalysis
- Antibiotic Resistance in Bacteria
- Chemical Reaction Mechanisms
- Histone Deacetylase Inhibitors Research
- RNA Interference and Gene Delivery
- Bioactive Compounds and Antitumor Agents
- Biochemical and Structural Characterization
- Antimicrobial Resistance in Staphylococcus
- Phytochemical compounds biological activities
- Synthesis and Reactions of Organic Compounds
- Mosquito-borne diseases and control
- Plant Disease Resistance and Genetics
National Chemical Laboratory
2014-2023
Academy of Scientific and Innovative Research
2016-2023
University of Minnesota
2022-2023
University Hospital Brno
2021
Masaryk University
2021
St. Anne's University Hospital Brno
2021
Council of Scientific and Industrial Research
2016
Known morpholine class antifungals (fenpropimorph, fenpropidin, and amorolfine) were synthetically modified through silicon incorporation to have 15 sila-analogues. Twelve sila-analogues exhibited potent antifungal activity against different human fungal pathogens such as Candida albicans, glabrata, tropicalis, Cryptococcus neoformans, Aspergillus niger. Sila-analogue 24 (fenpropimorph analogue) was the best in our hands, which showed superior fungicidal potential than fenpropimorph,...
The first total synthesis of the proposed structure solomonamide B has been achieved. However, 1H and 13C NMR spectral data synthesized compound was not exactly matching with that natural B. This prompted us to revise originally structure, in particular, stereochemistry nonpeptide part, which confirmed by its synthesis. During course synthesis, we have developed an interesting hydroxy group directed Wacker oxidation internal olefins a macrocyclic setting.
Abstract A simple and convenient method to access 4‐quinolone‐3‐carboxylic acid amides from indole‐3‐acetic through one‐pot oxidative cleavage of the indole ring followed by condensation (Witkop–Winterfeldt type oxidation) was explored. The scope confirmed with more than 20 examples successfully applied synthesis drug Ivacaftor, most expensive on market.
Herein, we report the total synthesis of solomonamide A along with its structural revision for first time. The natural product possesses very potent anti-inflammatory activity, and it contains a macrocyclic peptide having four consecutive stereocenters on an unnatural amino acid component. key features in present include application Evans aldol reaction, ligand-free Heck macrocyclization chemoselective oxidations. challenging task fixing stereochemistry OH at C5-position was accomplished...
Nosocomial infections caused by resistant Gram-positive organisms are on the rise, presumably due to a combination of factors including prolonged hospital exposure, increased use invasive procedures, and pervasive antibiotic therapy. Although stewardship infection control measures helpful, newer agents against multidrug-resistant (MDR) bacteria urgently needed. Here, we describe our efforts that led identification 5-amino-4-quinolone
To identify novel antitrypanosomal agents based on Janadolide, a potent macrocyclic polyketide–peptide hybrid, macrolactonization strategy was explored. We prepared des-tert-butyl Janadolide and evaluated its activity. Our findings suggest that the tert-butyl group is necessary for desired bioactivity.
Chandipura Virus (CHPV), a negative-stranded RNA virus belonging to the Rhabdoviridae family, has been previously reported bring neuronal apoptosis by activating several factors leading neurodegeneration. Following infection of central nervous system, microglia, ontogenetic and functional equivalents macrophages in somatic tissues gets activated starts secreting chemokines, thereby recruiting peripheral leukocytes into brain parenchyma. In present study, we have systemically examined effect...
In an attempt towards understanding stereo-structure activity relationships (SSARs), we have prepared eight possible stereoisomers of solomonamide macrocycles, in particular, by changing the stereochemical pattern non-peptide fragment AHMOA. Here, demonstrated different ways to construct three contiguous chiral centers present B macrocycle using substrate/reagent-controlled methods. These methods involve Brown crotylation, NHK reaction and Evans aldol addition as key steps synthesize...
An improved method for the synthesis of a new quinolone class antibiotics, which are exceptionally potent against gram-positive bacteria, has been developed and structure confirmed by single-crystal X-ray analysis. In course synthesis, using either Chan-Lam coupling or Buchwald-Hartwig amination, we have shown that careful choice protecting group at C4 position quinoline is required selective amination C5 subsequent deprotection to avoid formation novel pyrido[4,3,2-
Solomonamides, a pair of macrocyclic peptide natural products originating from marine sources, have garnered significant attention within the synthetic community owing to their marked anti-inflammatory efficacy and intricate molecular architectures. In this paper, we present very detailed investigation into solomonamides, including challenges associated with total synthesis, evolution our strategies, structural reassignment, synthesis all possible stereoisomeric macrocycles, biological...
We report synthesis of two diastereomeric structures previously proposed for the complex secondary metabolite pseurotin A2. Both were accessed from same building blocks taking advantage a stereodivergent nickel(II)-diamine-catalyzed 1,4-addition chiral 2-alkoxycarbonyl-3(2H)-furanone. Late-stage Csp-Csp3 cross-coupling highly functionalized bromoalkyne featured in A2 side-chain assembly. The work supports 2016 stereochemical revision and represents first chemical this natural product.
Vigabatrin is a potent inhibitor of gamma‐aminobutyric acid (GABA) catabolism used for the treatment epilepsy. Here we have synthesized both enantiomers drug vigabatrin in five steps from known intermediates using Wittig olefination and pyrolytic elimination as key steps. The target compounds are gram scale amounts with >98 % enantiopurity.
Abstract In search of novel antitrypanosomal agents based on hoshinolactam (IC 50 =3.9 nM), we disclose the synthesis and biological evaluations 14 different analogues natural product using combinations acids lactams. Antitrypanosomal activity assays revealed that synthesized were less potent than parent product.
Abstract 4‐Oxoquinoline‐3‐carboxamides are simply and conveniently obtained from 3‐indoleacetamides by one‐pot oxidative cleavage of the indole ring subsequent condensation (Witkop—Winterfeldt oxidation).