112346-93-7Relevant academic research and scientific papers
New nodularins: A general method for structure assignment
Namikoshi,Choi,Sakai,Sun,Rinehart,Carmichael,Evans,Cruz,Munro,Blunt
, p. 2349 - 2357 (1994)
A general method has been developed for assigning the structures of nodularin, a potent hepatotoxin, tumor promoter, and protein phosphatase inhibitor, and minor components isolated from a cultured and a bloom sample of the cyanobacterium Nodularia spumigena. It consists of (1) FABMS analysis (determination of molecular weight and molecular formula), (2) 1H NMR spectroscopy on the parent compound and chiral GC analysis of an acid hydrolyzate (identification and stereochemistry of amino acid components), (3) ozonolysis followed by NaBH4 reduction (conversion to a linear peptide), and (4) FABMS/CID/MS analyses of the linear peptide and the parent compound (sequence analysis). The method has been employed in assigning structures to three new nodularins (2-4) and can be applied to other cyclic peptides containing α,β-dehydroamino acid unit(s), especially the related microcystins, cyclic heptapeptide hepatotoxins. Two nodularins, [DMAdda3]nodularin (2) and [(6Z)Adda3]nodularin (3), were obtained from a bloom sample collected from Lake Ellesmere (New Zealand), and [D-Asp1]nodularin (4) was isolated from cultured cells (strain L-575). The LD50s of 2 and 4 were 150 and 75 μg/kg (ip, mice), respectively, but 3 did not show apparent toxicity at 2.0 mg/kg.
Synthesis of optically active 2-alkyl-3,4-iminobutanoic acids. β-amino acids containing an aziridine heterocycle
Park,Tian,Kim
, p. 3696 - 3703 (2007/10/03)
All four stereoisomers of 2-alkyl-3,4-iminobutanic acid, a novel class of β-amino acids bearing a chemically versatile aziridine ring, were synthesized starting with aspartic acid. The synthetic strategy involves the introduction of an alkyl group at the β-position of fully protected optically active aspartic acid followed by the construction of an aziridine ring making use of the α-carboxylate and α-amino groups. The α-carboxylate was reduced to the corresponding alcohol, which was then subjected to cyclization to form an aziridine ring with the N-protected amino group. Removal of the protection groups yielded the target compounds.
DEVELOPMENT OF CHIRAL β-DICARBONYL EQUIVALENTS. ENANTIODIVERGENT ALKYLATION OF ASPARTIC ACID.
McGarvey, Glenn J.,Hiner, Roger N,Matsubara, Yoshio,Oh, Taeboem
, p. 2733 - 2736 (2007/10/02)
L-Aspartic acid has been converted to derivatives which undergo alkylation reactions with stereoselectivities that are enantiomerically complimentary.
