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1.
The proton and carbon spectra of new 2,4‐diaryl‐substituted cycloalkyl[d]pyrimidines prepared in a simple one‐pot reaction, are reported. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

2.
The complete 1H and 13C assignments of eight bioactive indeno[1,2‐b]indole‐10‐one derivatives were accomplished by the combined use of one‐dimensional and two‐dimensional NMR experiments. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

3.
The thermodynamic products (ε‐lactams) of the degradation of ten different spirocyclic oxaziridines were analyzed by 1H and 13C NMR spectroscopy. The preferred conformations were determined by examining the homonuclear spin–spin coupling constant and the chemical shift effects of the N‐substituent and the alkyl group of the aliphatic ring on 1H and 13C NMR spectra. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
Chalcones are of interest to medicinal chemists because their structures can be easily modified with various functional groups. The syntheses and biological activities of chalcones from natural sources are well known. In this study, 24 2′‐hydroxychalcones bearing methoxy substituents were synthesized, among which five are new. The NMR data for all synthesized chalcones are described for the first time. The complete assignments of the 1H and 13C NMR data can be used for the identification of newly discovered and widely isolated, synthesized chalcones. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

5.
The 1H and 13C NMR spectroscopic data for alkyl 4‐aryl‐6‐chloro‐5‐formyl‐2‐methyl‐1,4‐dihydopyridine‐3‐carboxylates were fully assigned by combination of one‐ and two‐dimensional experiments (DEPT, HMBC, HMQC, COSY, NOE). Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

6.
Some novel 1, 2, 4-triazolo[3,4-b][1,3,4]thiadiazines derivatives were synthesized. The complete (1)H and (13)C NMR chemical shift assignments were analyzed on one- and two-dimensional NMR techniques, including DEPT, NOE-DIF, COSY, HMBC, and HSQC.  相似文献   

7.
The complete assignment of the 1H and 13C NMR spectra of the diastereomeric pairs of some α‐arylsulfinyl‐substituted N‐methoxy‐N‐methylpropionamides with the substituents methoxy, methyl, chloro, nitro is reported. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

8.
Nine flavonol derivatives were studied. Previously reported NMR data of three of these derivatives were corrected. We report complete assignments of the NMR data for six flavonol derivatives not previously studied.  相似文献   

9.
We report the total assignments of the 13C and 1H NMR spectra of some 4‐methyl‐2‐oxo‐(2H)‐pyrido[1,2‐a]pyrimidine and 2‐methyl‐4‐oxo‐(4H)‐pyrido[1,2‐a]pyrimidine derivatives. The products were characterized by 1H and 13C NMR and reported data for similar compounds. No comparative data for the two sets of isomeric compounds with respect to 13C and 1H NMR have been reported to date. We made some detailed studies of the 2D NMR spectra of these compounds and observed that assignments made for non‐protonated carbon atoms by us and those reported in the literature for similar compounds need correction. The revised assignments were made on the basis of heteronuclear single quantum correlation (HSQC) and heteronuclear multiple bond correlation (HMBC) techniques. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

10.
1H and 13C NMR data for 13 nitrohistidine derivatives are reported, providing a diagnostic method for the elucidation of the N1‐( 2 ) and the N3‐substituted ( 3 ) regioisomers. Spectral assignments of constrained surrogates of His ( 4 ) and of the His–Gly dipeptide ( 5 and 6 ) are also described. The structure of the compounds was confirmed by NOESY and heteronuclear (13C, 1H) short‐ and long‐range correlation experiments. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

11.
An NMR study of 11 naturally occurring abietane diterpenoids is described. In addition to one‐dimensional NMR methods, including DPFGSE 1D‐NOE spectra, two‐dimensional shift‐correlated experiments [1H,1H COSY, 1H,13C‐gHSQC 1J(C,H) and 1H,13C‐gHMBC nJ(C,H) (n = 2 and 3)] were used for the complete and unambiguous 1H and 13C chemical shift assignments of these substances. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

12.
13.
The complete 1H and 13C NMR assignments of four series pyrido[4,3‐d]pyrimidine derivatives were achieved by combination of one and two‐dimensional NMR experiments, and the NMR signals of these compounds were analyzed and compared. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

14.
The 1H and 13C NMR spectra of six 5-substituted 2-azabicyclo[2.2.2]octane derivatives were fully assigned by COSY and HSQC experiments.  相似文献   

15.
1H, 13C and 15N NMR chemical shifts of 10 substituted pyrazolo[1,5‐a]pyrimidines were assigned based on DQF 1H, 1H COSY, PFG 1H, 13C HMQC and PFG 1H,X (X = 13C and 15N) HMBC experiments and on literature data. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

16.
(1)H and (13)C NMR spectroscopic data for 5alpha-androstanes and halo-5alpha-androstanes with different substituents at positions C-3, C-9, C-11 and C-17 were examined and assigned by a combination of 1D and 2D NMR experiments. The substituent effects on the (13)C chemical shifts were compared with those of epi-androsterone, used as a reference compound. The coupling constants (n)J((19)F,(13)C) were measured for compounds 6, 8, 11 and 14.  相似文献   

17.
18.
Detailed assignments of 1H and 13C NMR spectral data for 14 cyclopentane derivatives are reported. The assignments are based on 1D 1H and 13C NMR and on 2D shift‐correlated [1H, 13C‐HMQC], J‐resolved and NOEDIF experiments. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

19.
1H and 13C NMR spectroscopic data for 4-aryl-3,4-dihydro-6-methyl-2(1H)pyridone derivatives were fully assigned by a combination of one- and two- dimensional experiments (DEPT, HMBC, HMQC, COSY, NOE).  相似文献   

20.
Ten 3‐methylflavone derivatives were studied. Previously reported NMR data of some derivatives were corrected and/or completed, including the complete assignment of the two known natural derivatives. The complete 1H and 13C NMR assignments were achieved by combination of one‐dimensional and two‐dimensional NMR experiments. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

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