We report the total syntheses of (-)-indolactam V and the C7-substituted indolactam alkaloids (-)-pendolmycin, (-)-lyngbyatoxin A, and (-)-teleocidin A-2. The strategy for preparing indolactam V relies on a distortion-controlled indolyne functionalization reaction to establish the C4-N linkage, in addition to an intramolecular conjugate addition to build the conformationally-flexible nine-membered ring. The total synthesis of indolactam V then sets the stage for the divergent synthesis of the other targeted alkaloids. Specifically, late-stage sp-sp cross-couplings on an indolactam V derivative are used to introduce the key C7 substituents and the necessary quaternary carbons. These challenging couplings, in addition to other delicate manipulations, all proceed in the presence of a basic tertiary amine, an unprotected secondary amide, and an unprotected indole. Thus, our approach not only enables the enantiospecific total syntheses of four indolactam alkaloids, but also serves as a platform for probing complexity-generating and chemoselective transformations in the context of alkaloid total synthesis.
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http://dx.doi.org/10.1039/C4SC00256C | DOI Listing |
PLOS Glob Public Health
December 2024
Center for Reproduction and Population Health Studies, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria.
Introduction: Substance use is a growing public health concern in West Africa, contributing to significant morbidity, mortality, and socioeconomic challenges. Despite the increasing prevalence, comprehensive data on the patterns and factors influencing substance use in the region remain limited. This systematic review and meta-analysis aim to synthesize existing research on the prevalence and patterns of substance use in West Africa, providing critical insights for developing targeted interventions and policies.
View Article and Find Full Text PDFEur J Nutr
December 2024
Department of Medicine, University of Otago, PO Box 56, Dunedin, 9016, New Zealand.
Background: Legumes are widely considered one of the most beneficial food groups to consume. They are high in fibre and plant-based protein as well as naturally low in sodium, saturated fats, and sugars. However, legumes do not feature prominently in the modern diet, and previous evidence syntheses show inconsistent results on cardiometabolic risk profile when increasing legume intakes.
View Article and Find Full Text PDFMicrob Pathog
December 2024
Davis Pharmaceutical Laboratories, 121, industrial triangle area, kahuta road, Islamabad.
This study explores the potential antagonistic effects of selenium-doped zinc oxide nanoparticles (Se-ZnO NPs), synthesized through a sustainable approach, on maize charcoal rot induced by the fungus Macrophomina phaseolina. Se-ZnO-NPs were prepared using the rhizobium extract of Curcuma longa and characterized for their physicochemical properties. Characterization included various in vitro parameters such as FTIR, ICP-MS, particle size, PDI, and zeta potential.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
December 2024
Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, 163 Horria Ave. El-Shatby, P.O. Box 832, Alexandria, Egypt.
Phenol is a highly concerning pollutant in petrochemical industrial wastewater. It is extremely poisonous, carcinogenic, and persistent, therefore, it bioaccumulates in the food chain reaching humans, where it causes acute irritation to the skin, eyes, and respiratory tract, as well as chronic effects on the liver, kidneys, and nervous system. It spills or leaks easily into surface water or groundwater sources, leading to the creation of other harmful substituted compounds.
View Article and Find Full Text PDFNat Commun
December 2024
Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
The functionalized polycycle with densely contiguous tertiary stereocenters is a formidable challenge in synthesizing the parvistemoline family of Stemona alkaloids. We herein report their catalytic, asymmetric total syntheses in 13-14 steps from commercially available 2-(methoxycarbonyl)-pyrrole, featuring the development and deployment of an Ir/Pd-synergistically-catalyzed allylation of α-non-substituted keto esters with secondary aryl-substituted alcohols, stereodivergently accessible to four stereoisomers. Using chiral Pd-enolate and Ir π-allyl complex under neutral conditions, no epimerization occurs.
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