1993 Fiscal Year Final Research Report Summary
SENSITIVITY-ENHANCED DETECTION OF QUATERNARY CARMONS BASED ON CONTRIBUTION OF HETERONUCLEI AND ITS APPLICATION TO NATURAL PRODUCT ANALYSIS
Project/Area Number |
04660127
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
製造化学・食品
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Research Institution | HOKKAAIDO UNIVERSITY |
Principal Investigator |
KAWABATA Jun HOKKAIDO UNIVERSITY, FACULTY OF AGRICULTURE, ASSOCIATE PROFESSOR, 農学部, 助教授 (60142197)
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Project Period (FY) |
1992 – 1993
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Keywords | NMR / DEPT C-C Relay / Composite Pulse / Spectrum Editing / Long-range C-C Correlation |
Research Abstract |
A novel sensitivity-enhanced ^<13>C-^<13>C observation method, DEPT C-C relay, has been invented. This sequence is of value for selective detection of CH-C_q, CH_2-C_q and CH_3-C_q connectivities at quaternary carbons (c_q) with the aid of DEPT spectrum editing technique. The resonance-offset varying with phase distortion, which is especially a problem in high field instruments, was efficiently compensated by using symmetric phase-alternating composite ^<13>C pulses. Moreover, construction of CH, CH_2 and CH_3 subspectra by DEPT spectrum editing made it possible to detect the ^<13>C-^<13>C satellite signals even at the protonated carbon sites since the strong contribution of the single quantum coherence derived from ^<1j>CH also underwent the selection by the editing. Furthermore, a long-range J version of the above methos using ^<1J>CH^<betaJ>CC or ^<3J>CH^<betaJ>CC relay has also been accessible. By the method, magnetization of proton could be transferred to a remote carbon which locates six-bond away from the starting proton. Magnetization transfer through heteronuclear NOE and a novel ID omega_1 hetero half-filtered CH correlation method, PASS(paired satellite selection), have also been proposed. By the latter method, accurate determination of long-range ^JCH values has made possible
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