An approach to chiral tetrahydrofuran and tetrahydropyran derivatives based on the sequential use of an asymmetric Horner-Wadsworth-Emmons reaction and a cyclization step is presented. The approach is both stereochemically and structurally versatile since three different cyclization methods can be employed starting from the same HWE product: (i) palladium-catalyzed substitution, (ii) hetero-Michael addition, or (iii) epoxide opening. The asymmetric HWE reaction controls the absolute configuration of the ultimate product, whereas the relative configuration is controlled by the combined influence of the geometric selectivity in the HWE reaction and the stereochemistry of the respective cyclization method.
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Mini Rev Med Chem
January 2025
Department of Physiology and Pharmacology Vittorio Erspamer, Sapienza University of Rome, 00161, Rome, Italy.
Currently, the synthesis of bioactive sulfonamides using amino acid as a starting reagent has become an area of research interest in organic chemistry. Over the years, an amine-sulfonyl chloride reaction has been adopted as a common step in traditional sulfonamide synthetic methods. However, recent developments have shown amino acids to be better precursors than amines in the synthesis of sulfonamides.
View Article and Find Full Text PDFChem Asian J
January 2025
Kasetsart University - Bangkhen Campus: Kasetsart University, Chemistry, 50, Department of Chemistry, Faculty of Science, Kasetsart UNiversity, Ladyao, Chatu, 10900, Bangkok, THAILAND.
(+)-Febrifugine, a natural antimalarial compound with a promising therapeutic profile, has become a hot target for synthetic chemists seeking to optimize its biological activity and expand its therapeutic applications. In this research, we present a stereocontrolled synthesis of (+)-febrifugine using both azide and azide-free approaches. Starting from the commercially available chiral pool precursor, d-glucose, the synthesis was completed in 20 steps for both approaches.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
Lymphedema, a severe and complex inflammatory disease caused by lymphatic system insufficiency and impeded lymphatic drainage that causes an enormous physical and psychological burden on patients and may even lead to death, has long been a challenging issue in the medical field. Clinically, conventional approaches including surgical treatment and conservative treatment have been employed for lymphedema therapy, but their curative effect is still unsatisfactory because of high operational difficulty, high cost, and long-term reliance. In this study, a novel kind of piezoelectric microneedle driven by ultrasound (US) is proposed to regulate macrophage polarization and remodel the pathological inflammatory microenvironment in a noninvasive manner, thereby promoting lymphatic regeneration and improving lymphedema.
View Article and Find Full Text PDFAnal Chem
January 2025
Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
This study tackles the challenge of enantiodifferentiation of nitrile compounds, which is typically difficult to resolve using nuclear magnetic resonance (NMR) due to the significant distance between the chiral center and the nitrogen atom involved in molecular interactions. We have developed novel chiral F-labeled probes, each featuring two chiral centers, to exploit the "match-mismatch" effect, thereby enhancing enantiodiscrimination. This strategy effectively differentiates chiral analytes with quaternary chiral carbon centers as well as those with similar substituents at the chiral center.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune-411008, India.
We report the stereoselective total synthesis of kavaratamide A, a linear lipodepsipeptide from the cyanobacterium (collected in Kavaratti, India), and its unnatural C25-epimer. The convergent approach employs Keck asymmetric allylation to construct the chiral β-hydroxy carboxylic acid fragment [(3)-HDA; 3-hydroxydecanoic acid], while the peptide unit was assembled from L-Val, -Me-L-Ala, ()-Hiva, and ()-Pr--Me-pyr using well-orchestrated coupling methods to prevent racemization. Modifications to the Keck allylation conditions enabled the synthesis of the C25-epimer with good yield.
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