M. Hatsu, H. Naganawa, T. Aoyagi
Dec 25, 1992
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0
Influential Citations
3
Citations
Journal
The Journal of antibiotics
Abstract
peptidase). In this paper, the structure determination of pyrizinostatin is reported. Pyrizinostatin was obtained as colorless crystals, and its molecular formula was established as CnH15N5O4 by HRFAB-MS and elemental analysis. The IR spectrum exhibited strong absorption at 1680cm" 1 suggesting the presence of amide bond in the molecule (Fig. 2). The UV spectra showed a maximumat 280nm (s 4,600) in MeOH. The 13C and XHNMRdata for pyrizinostatin are summarized in Table 1. In the 13C NMRspectrum, the signals of 1 1 carbons were resolved and assigned to four methyl carbons, one methylene carbon, one quaternary carbon and five quaternary sp2 carbons by DEPTexperiment. In the *H NMRspectrum, characteristic signals due to four isolated methyl groups were observed, and the three methyl groups could be assigned to TV-methyl protons based on their 13C and *H chemical shifts. One exchangeable proton signal (S 5.75) was attributed to be NH proton because it gave positive color reaction with Greig-Leaback reagent2). All of the proton signals of pyrizinostatin was located, and then the proton-carbon correlations were obtained by a heteronuclear multiple-bond correlation (HMBC)3) experiment and assignment of *H and 13C NMR spectra were elucidated. The summaryof the 1H-13C long range coupling by HMBCmeasurements on pyrizinostatin is shown in Fig. 3. The structure of pyrizinostratin was determined by crystal X-ray diffraction analysis. A colorless