Aristolochic Acids and Aristolactams

Plants belonging to the genns of Aristolochia are rich in aristolochic acids and aristolactams. 

Aristolochic acids and aristolactams possess skeleta (66) and (67), respectively, and are often found in the same plant. The aristolochic acids are among the small group of natural products incorporating a nitro-function. Compounds belonging to these two classes are non-basic, but can nevertheless be classified as alkaloids since they are derived from in vivo oxidation of aporphines. The last review on this dual topic appeared in 1961. ... 

Aristolochic acids and aristolactams presently known and characterized, together with their sources, include (68)—(83). 

Kampo medicines in which A.fangchi root or A. manshuriensis stem may be misused [492], Moreover, LC-PDA and LC-EIMS detection methods both were effective in distinguishing AAI (5) and AAII (5) peaks by their spectra. Very recently, we have reported the extensive analysis of aristolochic acids and aristolactams in the various Chinese medicinal plants and crude drugs using different techniques. A method has been developed using reversed phase liquid chromatography coupled with atmospheric pressure chemical ionization (APCI) tandem mass spectrometry under the positive ion detection mode [LC/(+)APCI/MS/MS] to determine the amount of AA-1(5) in Xinxin, a traditional Chinese medicine that originate from nine Asarum species... 

Fig. 32.15. Biogenesis of aristolochic acids and aristolactams (modified from Cordell, 1981 used by permission of the author).

Aristolochic acids and aristolactams occur mostly within the family of Aristolochiaceae, although cepharanone-A and aristolactam-Bll were found in Stephania cepharantha Y. Hayata (Menispermaceae), and doryflavine was obtained from Doryphora sassafras Endlicher (Monimiaceae). There is a possibility that aristolochic acid-B may correspond to aristolochic acid-D. 

The PMR spectra of the aristolochic acids and aristolactams are usually run in DMSO-de. Pyridine-dg has also been used in connection with the aristolactams. 

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