Xiang, Wen-Xin; Liu, Qing; Li, Xiao-Man; Lu, Chun-Hua; Shen, Yue-Mao published the artcile< Four pairs of proline-containing cyclic dipeptides from Nocardiopsis sp. HT88, an endophytic bacterium of Mallotus nudiflorus L>, Application of C11H18N2O2, the main research area is cyclic dipeptide isolation structure activity Nocardiopsis; Mallotus nudiflorus (L.) Kulju & Welzen; Nocardiopsis sp. HT88; dd-diketopiperazines; proline (or hydroxyproline)-containing cyclic dipeptides.
Strain HT88 was isolated from the fresh stems of Mallotus nudiflorus, and it was identified as Nocardiopsis sp. by analyzing its morphol. and the 16S rRNA sequence. The extracts of fermented HT88 showed potent antimicrobial activities. Bioassay guided separation of extracts led to 8 proline (or hydroxyproline, Hyp)-containing cyclic dipeptides. Their structures were determined by 1D and 2D NMR spectroscopy and ESI mass spectrometry and further comparison with existing 1H and 13C NMR, m.ps. and sp. rotation data. The 8 2,5-diketopiperazines (DKPs) were identified as cyclo(L-Pro-L-Leu), cyclo(Pro-Leu), cyclo(L-trans-Hyp-L-Leu), cyclo(D-trans-Hyp-D-Leu), and cyclo(D-Pro-L-Phe), cyclo(L-Pro-L-Phe) and cyclo(D-cis-Hyp-L-Phe), cyclo(L-trans-Hyp-L-Phe). Up to date, this is the 1st isolation of 4 pairs of proline-based DKPs from Nocardiopsis sp.
Natural Product Research published new progress about Antibacterial agents. 2873-36-1 belongs to class pyrazines, and the molecular formula is C11H18N2O2, Application of C11H18N2O2.