AI Article Synopsis
- The synthesis of erythronolide A, a key component of erythromycin A, involves intermediates derived from seco-acids through a reaction with MNBA and DMAP.
- The study assesses the efficiency of MNBA-based lactonization by comparing it with other established methods, revealing varying success rates based on substrate structure.
- Key findings include optimal yields for specific conformations and conditions, with monomeric lactones produced efficiently, while some stable substrates favored dimeric forms.
Article Abstract
Various intermediates for the synthesis of erythronolide A, an aglycon of erythromycin A, are prepared from the corresponding seco-acids using 2-methyl-6-nitrobenzoic anhydride (MNBA) in the presence of 4-(dimethylamino)pyridine (DMAP) with or without triethylamine. The efficiency of the MNBA lactonization is assessed by studying this method and comparing the results with those of the other established macrocyclization protocols. It has been finally concluded that (i) the conformationally appropriate substrate for the monomeric cyclization gave the desired lactone in excellent yield under mild reaction conditions in the presence of MNBA and DMAP, (ii) the highly-strained substrate for the cyclization also afforded the monomeric lactone in relatively good yield at 100 degrees C in toluene, and (iii) the seco-acid having stable linear conformation, which preferred dimerizing more than forming the monomeric lactone, provided the corresponding diolide in high yield with the constant ratio of the monomer to dimeric lactone (approximately 1/5).
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/tcr.200900017 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Methods for Visualizing and Quantifying Cholesterol Distribution in Mammalian Cells Using Filipin and D4 Probes.
Methods Mol Biol
December 2024
Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), UMR 7104, CNRS, Inserm, Université de Strasbourg, Illkirch, France.
Cholesterol is a key component of biological membranes and, like many cellular lipids, is unevenly distributed among organelles. Disruptions in cholesterol trafficking are associated with various pathologies, including lysosomal lipid storage disorders, often characterized by intracellular cholesterol accumulation. A significant challenge in studying cholesterol trafficking is the lack of easy methods to trace this molecule in situ.
View Article and Find Full Text PDFGrafting Buffer Layer Strategy onto the Nanofiltration Membrane to Enhance Antifouling Properties toward Highly Efficient Desalination.
Langmuir
December 2024
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
Water treatment and seawater desalination are two areas in which nanofiltration (NF) membranes have gained significant attention. The permeability and contamination resistance of NF membranes are crucial for their application in ion separation. Herein, a zwitterion monomeric -sulfobutylpiperazine (PIPBS) was designed and synthesized through an in situ ring-opening reaction between 1,4-butylsulfonic acid lactone and piperazine.
View Article and Find Full Text PDFUnprecedented nor-seco-diterpene lactones inhibited osteogenic differentiation of valve interstitial cells.
Bioorg Chem
December 2024
The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, Shenzhen 518035, China; Wu Zhengzhi Academician Workstation, Ningbo College of Health Sciences, Ningbo 315800, China. Electronic address:
Article Synopsis
- - The study identifies two new diterpene lactones, eufislactones A and B, isolated from the roots of Euphorbia fischeriana, alongside a new compound and fifteen known derivatives.
- - The structural analysis of these compounds was performed using various methods including spectroscopy and X-ray diffraction, revealing their unique chemical configurations.
- - Eufislactone A has shown a significant effect on inhibiting the differentiation of human valvular interstitial cells, indicating its potential to help prevent calcific aortic valve disease.
mTORC1 pathway activity biases cell fate choice.
Sci Rep
September 2024
Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
Pluripotent stem cells can differentiate into distinct cell types but the intracellular pathways controlling cell fate choice are not well understood. The social amoeba Dictyostelium discoideum is a simplified system to study choice preference as proliferating amoebae enter a developmental cycle upon starvation and differentiate into two major cell types, stalk and spores, organised in a multicellular fruiting body. Factors such as acidic vesicle pH predispose amoebae to one fate.
View Article and Find Full Text PDFDivergent effects of azithromycin on purple corn (Zea mays L.) cultivation: Impact on biomass and antioxidant compounds.
PLoS One
August 2024
Escuela Profesional de Ingeniería Ambiental de la Universidad Nacional de Moquegua, Urb Ciudad Jardín-Pacocha-Ilo, Perú.
The present study assessed the impact of using irrigation water contaminated with Azithromycin (AZM) residues on the biomass and antioxidant compounds of purple corn; for this purpose, the plants were cultivated under ambient conditions, and the substrate used consisted of soil free from AZM residues, mixed with compost in a ratio of 1:1 (v/v). The experiment was completely randomized with four replications, with treatments of 0, 1, 10, and 100 μg/L of AZM. The results indicate that the presence of AZM in irrigation water at doses of 1 and 10 μg/L increases the weight of dry aboveground biomass, while at an amount of 100 μg/L, it decreases.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!