title: Nigrosphaerin A a new isochromene derivative from the endophytic fungusNigrospora sphaerica.
abstract: Nigrosphaerin A, a new isochromene derivative (1), was isolated from the endophytic fungusNigrospora sphaericaand chemically identified as 3-(3,4-dihydroxyphenyl)-4,6,8-trihydroxy-1H-isochromen-1-one-6-O-β-d-glucopyranoside. In addition nineteen known compounds (2-20) were isolated from the same fungus and chemically identified. Compounds (1-3,5, and7-16) were isolated for the first time from this fungus.In vitroantileukemic, antileishmanial, antifungal, antibacterial and antimalarial activities of (1-20) were examined. Compounds5,7,9and10showed good antileukemic activity against HL60 cells with IC50values of 0.03, 0.39, 0.2 and 0.4 μg/mL, respectively and against K562 cells with IC50values of 0.35, 0.35, 0.49 and 0.01 μg/mL, respectively. Compounds3,4and6showed moderate antileishmanial activity with IC50values of 30.2, 26.4 and 36.4 μg/ml, respectively. Compound7showed moderate antifungal activity againstCryptococcus neoformanswith IC50value of 14.8 μg/mL.
authors.affiliation: National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA; Department of Pharmacognosy, Faculty of Pharmacy, University of Al-Azhar, Cairo, Egypt.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Metwaly
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, University of Al-Azhar, Cairo, Egypt.
authors.forename: Hazem A
authors.initials: HA
authors.lastname: Kadry
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, University of Al-Azhar, Cairo, Egypt.
authors.forename: Atef A
authors.initials: AA
authors.lastname: El-Hela
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, University of Al-Azhar, Cairo, Egypt.
authors.forename: Abd-Elsalam I
authors.initials: AI
authors.lastname: Mohammad
authors.affiliation: National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
authors.forename: Guoyi
authors.initials: G
authors.lastname: Ma
authors.affiliation: Department of Medicinal Chemistry, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Cutler
authors.affiliation: National Center for Natural Products Research, School of Pharmacy, The University of Mississippi, University, MS 38677, USA; Department of Pharmacognosy, School of Pharmacy, The University of Mississippi, University, MS 38677, USA.
authors.forename: Samir A
authors.initials: SA
authors.lastname: Ross
keywords: Antileishmanial; Antileukemic; Isochromene; Nigrosphaerin A; Nigrospora sphaerica