74124-69-9Relevant articles and documents
Biosynthetic intermediates of the tetradehydro cyclic dipeptide albonoursin. Produced by Streptomyces albulus KO-23
Kansaki,Yanagisawa,Nitoda
, p. 1257 - 1264 (2000)
The cell-free extract of an albonoursin-producing strain Streptomyces albulus KO-23 catalyzes the conversion of cyclo(L-Leu-L-Phe) (1) to albonoursin (2). At the early stage of this conversion, two compounds were newly formed prior to albonoursin synthesis in the reaction mixture. These compounds were isolated and identified as (Z)-3-benzylidene-6-isobutyl-2,5- piperazinedione (4) and (Z)-3-benzyl-6-isobutylidene-2,5-piperazinedione (3). The cell-free extract also catalyzed the conversion of compound 3 or 4 to albonoursin. From these results, albonoursin was found to be biosynthesized via these compounds from cyclo (L-Leu-L-Phe). These didehydro diketopiperazines exhibited no inhibitory activity toward the first cleavage of sea urchin embryo in contrast to the higher cytotoxicity for albonoursin, indicating that dehydrogenation at α,β-positions of both amino acid residues in diketopiperazines is required for cytotoxicity.
A NEW ROUTE TO (Z)-3-ALKYLIDENE-(S)-6-ALKYL-2,5-PIPERAZINEDIONES VIA N-CARBOXY-α-DEHYDROAMINO ACID ANHYDRIDES
Shin, Chung-gi,Yonezawa, Yasuchika,Ogawa, Kazumichi
, p. 2087 - 2089 (2007/10/02)
A new synthetic method for (Z)-3-alkylidene-(S)-6-alkyl-2,5-piperazinediones was accomplished by the coupling of N-carboxy-α-dehydroamino acid anhydrides with Boc-α-amino acid, followed by the deprotection of Boc group and by the ring expansion.