TY - JOUR
T1 - Welwitindolinones, Unusual Alkaloids from the Blue-Green Algae Hapalosiphon welwitschii and Westiella intricata. Relationship to Fischerindoles and Hapalinodoles
AU - Stratmann, Klemens
AU - Moore, Richard E.
AU - Patterson, Gregory M.L.
AU - Bonjouklian, Rosanne
AU - Deeter, Jack B.
AU - Shaffer, Stacey
AU - Smitka, Tim A.
AU - Smith, Charles D.
PY - 1994/11/1
Y1 - 1994/11/1
N2 - N-Methyl welwitindolinone C isothiocyanate (7), the major indole alkaloid in the blue-green algae (cyanobacteria) Hapalosiphon welwitschii W. & G. S. West UHIC-52-3 and Westiella intricata Borzi UH HT-29-1 (Stigonemataceae), is responsible for some of the multiple-drug-resistance (MDR) reversing activity in H. welwitschii and most of the insecticidal activity in W. intricata. The oxindole was isolated from the lipophilic extracts of the two cyanophytes and its structure and absolute stereochemistry determined by X-ray crystallography. Fourteen additional alkaloids were isolated from H. welwitschii as minor constituents, viz. a novel spiro oxindole, welwitindolinone A isonitrile (1), five tetracyclic oxindoles (1-6) related to 7, and eight biogenetically-related fischerindoles (8-11) and hapalindoles (12-15). In addition to 1, five other alkaloids were isonitriles and these six compounds collectively accounted for the fungicidal activity of H. welwitschii. The gross structures and relative stereochemistries of 1-6 and 8-15 were elucidated by spectral analysis. The biogenesis of these alkaloids is discussed.
AB - N-Methyl welwitindolinone C isothiocyanate (7), the major indole alkaloid in the blue-green algae (cyanobacteria) Hapalosiphon welwitschii W. & G. S. West UHIC-52-3 and Westiella intricata Borzi UH HT-29-1 (Stigonemataceae), is responsible for some of the multiple-drug-resistance (MDR) reversing activity in H. welwitschii and most of the insecticidal activity in W. intricata. The oxindole was isolated from the lipophilic extracts of the two cyanophytes and its structure and absolute stereochemistry determined by X-ray crystallography. Fourteen additional alkaloids were isolated from H. welwitschii as minor constituents, viz. a novel spiro oxindole, welwitindolinone A isonitrile (1), five tetracyclic oxindoles (1-6) related to 7, and eight biogenetically-related fischerindoles (8-11) and hapalindoles (12-15). In addition to 1, five other alkaloids were isonitriles and these six compounds collectively accounted for the fungicidal activity of H. welwitschii. The gross structures and relative stereochemistries of 1-6 and 8-15 were elucidated by spectral analysis. The biogenesis of these alkaloids is discussed.
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U2 - 10.1021/ja00101a015
DO - 10.1021/ja00101a015
M3 - Article
AN - SCOPUS:0027973653
SN - 0002-7863
VL - 116
SP - 9935
EP - 9942
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 22
ER -