Potent Inhibition of Oxidative Phosphorylation by Marine Natural Products

Pycnanthuquinone C, an Unusual 6,6,5-Tricyclic Geranyltoluquinone from the Western Australian Brown Alga Cystophora harveyi

“…(2′E)-2-(3′,7′-Dimethylocta-2′,6′-dienyl)-4-hydroxy-1-methoxy-6methylbenzene (5): yellow-orange oil; IR νmax (neat) 3383, 2921, 1727 cm -1 ; 1 H NMR (CDCl3, 300 MHz) δ 6.47 ( 1 H, s, H-5′), 6.46 ( 1 H, s, H-3′), 5.25 ( 1 H, tq, J ) 7.2, 1.1 Hz, H-2), 5.08 ( 1 H, tm, J ) 6.7, 1.3 Hz, H-6), 4.48 ( 1 H, bs, 1′-OH), 3.66 (3H, s, 1′-OCH3), 3.30 (2H, d, J ) 7.2 Hz, H-1), 2.23 (3H, s, 6′-CH3), 2.09 (2H, m, H-5), 2.04 (2H, m, H-4), 1.69 (3H, bs, 3-CH3), 1.66 (3H, bs, 7trans-CH3), 1.58 (3H, bs, 7cis-CH3); 13 (20), 190 (11), 175 (15), 163 (10), 151 (25), 137 (21), 123(58), 107 (6), 91 (13), 81 (16), 77 (15), 69 (59), 55 (21), 41 (100).…”

“…Species of the brown algal genus Cystophora are restricted to the cool temperate waters of Australasia and are prominent members of inter- and subtidal rocky shore communities. − Previous chemical investigation of the more common members of the genus has resulted in the isolation of phlorotannins, − acyclic and cyclic geranyl and farnesylacetone derivatives, resorcinols, phloroglucinols, methylene-interrupted polyenes, − and two meroditerpenoids . Several compounds isolated exhibit mild anti-inflammatory activity. , While numerous Cystophora species have extensive ranges along temperate Australasian coastlines, the waters of the southwest of Western Australia contain a number of endemic species, and it has been suggested that this area may be a site of active speciation within the genus…”

“…13 Several compounds isolated exhibit mild anti-inflammatory activity. 15,16 While numerous Cystophora species have extensive ranges along temperate Australasian coastlines, the waters of the southwest of Western Australia contain a number of endemic species, and it has been suggested that this area may be a site of active speciation within the genus. 2 There has been only one published chemical investigation of Cystophora species from Western Australian waters, and thus, as part of an ongoing investigation into the diverse chemistry and chemotaxonomy of the Cystophora genus, a collection of C. harVeyi Womersley (Cystoseiraceae) was made near Cape Leeuwin in Western Australia.…”

Pharmacological Properties of the Natural Marine Product Furospongin‐1

“…Since this early work, a large number of organic molecules have been isolated from the marine environment (Kaul & Daftari 1986), including compounds that affect energy metabolism (Jamieson et al 1980).…”

“…Pioneering marine research by Emerson and Taft (1945) and Bergmann and Freeny (1950), found marine organisms that contained secondary metabolites which were rare or absent in the terrestrial environment. Since this early work, a large number of organic molecules have been isolated from the marine environment (Kaul & Daftari 1986), including compounds that affect energy metabolism (Jamieson et al 1980). Furospongin-1 is a sesterterpene that contains two furan rings at either end of a carbon chain (Fig.…”