185201-02-9Relevant academic research and scientific papers
Stereoisomeric indole compounds, process for the preparation of the same, and use thereof
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Page column 11, (2010/11/30)
Novel stereoisomeric indole compounds of the formula (1), a process for the preparation the same, and use thereof wherein, Y represents the group wherein, X represents alkyl group having 1-5 carbon atom(s) (the alkyl group may be substituted with hydroxyl group, carboxyl group, amino group, methylthio group, mercapto group, guanidyl group, imidazolyl group or benzyl group), and R1and R2represent each independently hydrogen atom, alkyl group, aralkyl group, cycloalkyl group or aryl group;R represents hydrogen atom, alkyl group, aralkyl group, cycloalkyl group, aryl group, monovalent metal, amine or ammonium; and the symbol ‘*’ represents a position of an asymmetric carbon atom. The above-mentioned compounds can be prepared by condensing tryptophan with a stereoisomeric α-amino acid or carboxylic acid to form an amide form and subjecting or carboxylic acid to form an amide form and subjecting the amide form to oxidative cyclization to form an oxazole ring at once. The compounds exhibit; physiological activities such as inhibitory action against lipid peroxidation, and can be therefore utilized in the form of lipid peroxidation inhibitors containing the same as the active ingredient.
First total synthesis of martefragin A, a potent inhibitor of lipid peroxidation isolated from sea alga
Nishida, Atsushi,Fuwa, Mihoko,Fujikawa, Yukiko,Nakahata, Etsuko,Furuno, Asako,Nakagawa, Masako
, p. 5983 - 5986 (2007/10/03)
The first total synthesis of martefragin A, a potent inhibitor of lipid peroxidation isolated from sea alga, has been accomplished and the absolute configurations of two stereogenic centers were determined. Synthetic martefragin A, its stereo isomers, and some analogs showed strong inhibitory activity against lipid peroxidation rat liver microsome.
Total synthesis of zaragozic acid A (squalestatin S1). Degradation to a relay compound and reassembly of the natural product
Stoermer, Doris,Caron, Stephane,Heathcock, Clayton H.
, p. 9115 - 9125 (2007/10/03)
Zaragozic acid A (squalestatin S1) (1) was converted into the simpler derivative 2, which was reconverted into the natural product, thus establishing 2 as a viable relay compound for total synthesis of 1. The degradation consisted of formation of the tri-tert-butyl ester (3), from which the two side chains were sequentially removed to obtain 8. Aldehyde 8 was converted into dimethyl acetal 2 in standard fashion. The C6 acyl side chain 14 was prepared from (S)-2-methylbutanol ('active amyl alcohol'), and the desired 4S configuration was obtained by use of Evans asymmetric enolate methylation. The C1 alkyl side chain was prepared as stannane 23a from (R)-2-methyl-3-phenylpropanol (21). For conversion of 2 back into zaragozic acid A, the dimethyl acetal was first converted into the cyclic acetal 17, thus protecting the C7 hydroxyl group. The remaining hydroxyl group was then acylated with acid 14 to obtain 18, which was transformed into aldehyde 20. The C1 alkyl chain was elaborated by the addition of a chiral α-alkoxyorganocerium reagent, obtained from 23a, to aldehyde 20. The resulting mixture of diastereomeric secondary alcohols was converted into zaragozic acid A (1) in six steps.
