1. Antileishmanial Carbasugars from Geosmithia langdonii
- Author
-
Daneel Ferreira, A. M. Moharram, Samir A. Ross, Lourin G. Malak, Mohamed Ali Ibrahim, Pankaj Pandey, Robert J. Doerksen, and Babu L. Tekwani
- Subjects
0301 basic medicine ,Geosmithia langdonii ,Circular dichroism ,Magnetic Resonance Spectroscopy ,Stereochemistry ,Pharmaceutical Science ,01 natural sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Drug Discovery ,Animals ,Molecule ,Pharmacology ,Antiparasitic Agents ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Circular Dichroism ,Organic Chemistry ,Absolute configuration ,Carbasugars ,Nuclear magnetic resonance spectroscopy ,0104 chemical sciences ,030104 developmental biology ,Complementary and alternative medicine ,Hypocreales ,Molecular Medicine ,Specific rotation ,Sugars ,Two-dimensional nuclear magnetic resonance spectroscopy ,Leishmania donovani - Abstract
Two new carbasugar-type metabolites, (1 S,2 R,3 R,4 R,5 R)-2,3,4-trihydroxy-5-methylcyclohexyl-2',5'-dihydroxybenzoate (1) and (1 S,2 S,3 S,4 R,5 R)-4-[(2',5'-dihydroxybenzyl)oxy]-5-methylcyclohexane-1,2,3-triol (2), were isolated from the filamentous fungus Geosmithia langdonii isolated from cotton textiles from Assiut, Egypt. The structures of 1 and 2 were elucidated based on comprehensive 1D and 2D NMR and MS data. Compounds 1 and 2 showed antileishmanial activity against Leishmania donovani with IC50 values of 100 and 57 μM, respectively. The (1 S,2 R,3 R,4 R,5 R) absolute configuration of carbasugar 1 was assigned via 2D NMR and experimental and calculated electronic circular dichroism (ECD) data. Similarly, the tentative structure of compound 2 was shown to possess a (1 S,2 S,3 S,4 R,5 R) absolute configuration via comparing its experimental ECD data and the specific rotation with 1 as well as examining the energy-minimized 3D computational models of compounds 1 and 2.
- Published
- 2018