title: Bioactive Hydantoin Alkaloids from the Red Sea Marine Sponge Hemimycale arabica.
abstract: In the course of our continuing efforts to identify bioactive secondary metabolites from Red Sea marine invertebrates, we have investigated the sponge Hemimycale arabica. The antimicrobial fraction of an organic extract of the sponge afforded two new hydantoin alkaloids, hemimycalins A and B (2 and 3), together with the previously reported compound (Z)-5-(4-hydroxybenzylidene)imidazolidine-2,4-dione (1). The structures of the compounds were determined by extensive 1D and 2D NMR (COSY, HSQC and HMBC) studies and high-resolution mass spectral determinations. Hemimycalins A (2) and B (3) represent the first examples of the natural N-alkylated hydantoins from the sponge Hemimycale arabica. Compounds 1-3 displayed variable antimicrobial activities against E. coli, S. aureus, and C. albicans. In addition, compound 1 displayed moderate antiproliferative activity against the human cervical carcinoma (HeLa) cell line. These findings provide further insight into the chemical diversity as well as the biological activity of this class of compounds.
authors.affiliation: Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia. dyoussef@kau.edu.sa.
authors.forename: Diaa T A
authors.initials: DT
authors.lastname: Youssef
authors.affiliation: Natural Products Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia. lshalla@kau.edu.sa.|Suez Canal University Hospital, Suez Canal University, Ismailia 41522, Egypt. lshalla@kau.edu.sa.
authors.forename: Lamiaa A
authors.initials: LA
authors.lastname: Shaala
authors.affiliation: Department of Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah 21589, Saudi Arabia. kalshali@kau.edu.sa.
authors.forename: Khalid Z
authors.initials: KZ
authors.lastname: Alshali
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D005260:Female; D006367:HeLa Cells; D006801:Humans; D006827:Hydantoins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019156:Indian Ocean; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011161:Porifera / Q000378:metabolism*; D064210:Secondary Metabolism; D013211:Staphylococcus aureus / Q000187:drug effects; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy
chemical_list: D000470:Alkaloids; D000890:Anti-Infective Agents; D000970:Antineoplastic Agents; D006827:Hydantoins
keywords: HeLa cells; Hemimycale arabica; N-alkylated hydantoins; Red Sea sponge; antimicrobial and antiproliferative activities; hemimycalins A and B