Total synthesis and isolation of citrinalin and cyclopiamine congeners.
Many natural products that contain basic nitrogen atoms--for example alkaloids like morphine and quinine-have the potential to treat a broad range of human diseases. However, the presence of a nitrogen atom in a target molecule can complicate its chemical synthesis because of the basicity of nitrogen atoms and their susceptibility to oxidation. Obtaining such compounds by chemical synthesis can be further complicated by the presence of multiple nitrogen atoms, but it can be done by the selective introduction and removal of functional groups that mitigate basicity. Here we use such a strategy to complete the chemical syntheses of citrinalin B and cyclopiamine B. The chemical connections that have been realized as a result of these syntheses, in addition to the isolation of both 17-hydroxycitrinalin B and citrinalin C (which contains a bicyclo[2.2.2]diazaoctane structural unit) through carbon-13 feeding studies, support the existence of a common bicyclo[2.2.2]diazaoctane-containing biogenetic precursor to these compounds, as has been proposed previously.
Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Eduardo V
EV
Mercado-Marin
Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Pablo
P
Garcia-Reynaga
Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, CP 780, CEP 13560-970, Sao Carlos, SP, Brazil.
Stelamar
S
Romminger
Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, CP 780, CEP 13560-970, Sao Carlos, SP, Brazil.
Eli F
EF
Pimenta
Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, USA.
David K
DK
Romney
Department of Chemistry, University of California, Davis, CA 95616, USA.
Michael W
MW
Lodewyk
Department of Chemistry and Earth and Ocean Sciences, University of British Columbia, Vancouver, British Columbia, V6T IZI, Canada.
David E
DE
Williams
Department of Chemistry and Earth and Ocean Sciences, University of British Columbia, Vancouver, British Columbia, V6T IZI, Canada.
Raymond J
RJ
Andersen
Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, USA.
Scott J
SJ
Miller
Department of Chemistry, University of California, Davis, CA 95616, USA.
Dean J
DJ
Tantillo
Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, CP 780, CEP 13560-970, Sao Carlos, SP, Brazil.
Roberto G S
RGS
Berlinck
Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Richmond
R
Sarpong
D000470:Alkaloids / Q000096:biosynthesis / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification*; D001688:Biological Products / Q000138:chemical synthesis* / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D054836:Indolizidines / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D013237:Stereoisomerism
D000470:Alkaloids; D001688:Biological Products; D026121:Indole Alkaloids; D054836:Indolizidines; C554221:citrinalin B; D009584:Nitrogen; D010100:Oxygen