On Ruhemann's Purple

The 1H nmr spectrum previously reported for Ruhemann's Purple is shown to be inconsistent with the accepted structure of this material. The discrepancy with the reported 1H nmr spectrum is shown to be due to the presence of a major impurity, identified as hydrindantin. Spectra (1H nmr, 3C nmr, ir, uv–visible) of Ruhemann's Purple, its protonated analogue DYDA, and other ninhydrin relatives are reported, and structural conclusions are based on these spectral data.

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21,22-Disubstituted 18α,19βH-Ursane Derivatives with Oxabicyclooctane System in Ring E

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19930173 ◽

1993 ◽

Vol 58 (1) ◽

pp. 173-190 ◽

Cited By ~ 1

Author(s):

Eva Klinotová ◽

Jiří Klinot ◽

Václav Křeček ◽

Miloš Buděšínský ◽

Bohumil Máca

Keyword(s):

Spectral Data ◽

Spin Systems ◽

Coupling Constants ◽

Complete Analysis ◽

Nmr Spectrum ◽

Proton Proton ◽

H Nmr ◽

Proton Coupling ◽

C Nmr

Reaction of 3β-acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) and 20β,28-epoxy-21,22-dioxo-19α,19βH-ursan-3β-yl acetate (IIIb) with diazomethane afforded derivatives XII-XIV with spiroepoxide group in position 21 or 22, which were further converted into hydroxy derivatives XV and XVII. Ethylene ketals VIII-X were also prepared. In connection with the determination of position and configuration of the functional groups at C(21) and C(22), the 1H and 13C NMR spectral data of the prepared compounds are discussed. Complete analysis of two four-spin systems in the 1H NMR spectrum of bisethylenedioxy derivative Xb led to the proton-proton coupling constants from which the structure with two 1,4-dioxane rings condensed with ring E, and their conformation, was derived.

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Synthesis of 2-amino-5,7-dimethyl-4-oxopyrido[3,4-e]-1,3-thiazines

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19833426 ◽

1983 ◽

Vol 48 (12) ◽

pp. 3426-3432 ◽

Cited By ~ 4

Author(s):

Dušan Koščík ◽

Pavol Kristian ◽

Ondrej Forgáč

Keyword(s):

Spectral Data ◽

Chlorine Atom ◽

Mass Spectra ◽

High Reactivity ◽

Secondary Amines ◽

Dimroth Rearrangement ◽

H Nmr ◽

New Synthesis ◽

C Nmr

New synthesis of pyrido[3,4-e]-1,3-thiazines consisting in reaction of 2,6-dimethyl-4-chloronicotinoyl isothiocyanate with primary or secondary amines, or with benzaldehyde phenylhydrazone, is described. High reactivity of the chlorine atom does not allow isolation of the corresponding thioureas, arising as intermediates, except in the case of the benzylamino derivative. Structure of the products was unequivocally confirmed by their spectral data (IR, UV, 1H NMR, 13C NMR and mass spectra). The synthesized derivatives do not undergo the Dimroth rearrangement.

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Evaluation of Antinociceptive and Anti-Inflammatory Activities of a New Triterpene Saponin from Bauhinia variegata Leaves

Zeitschrift für Naturforschung C ◽

10.1515/znc-2009-11-1208 ◽

2009 ◽

Vol 64 (11-12) ◽

pp. 798-808 ◽

Cited By ~ 12

Author(s):

Mona A. Mohamed ◽

Madeha R. Mammoud ◽

Heiko Hayen

Keyword(s):

High Resolution ◽

Spectral Data ◽

Cinnamic Acid ◽

Cinnamic Acid Derivatives ◽

Triterpene Saponin ◽

H Nmr ◽

Antischistosomal Activity ◽

Bauhinia Variegata ◽

Anti Inflammatory ◽

C Nmr

A new triterpene saponin, named as 23-hydroxy-3α-[O-α-L-1C4-rhamnopyranosyl-(1´´4´)- O-α-L-4C1-arabinopyranosyl-oxy]olean-12-en-28-oic acid O-α-L-1C4-rhamnopyranosyl- (1´´´´´→4´´´´)-O-β-D-4C1-glucopyranosyl-(1´´´´→6´´´)-O-β-D-4C1-glucopyranosyl ester (9), was isolated from the leaves of Bauhinia variegata Linn. In addition, six flavonoid compounds along with two cinnamic acid derivatives were isolated and identified based on their chromatographic properties, and chemical and spectral data (ESI-high resolution-MSn, 1H NMR, 13C NMR, 1H-1H COSY, HSQC, and HMBC). Compound 9 was found to be nontoxic (LD50) and to have significant anti-inflammatory and antinociceptive activities. It also showed a slight antischistosomal activity.

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Synthesis, Characterization, and Biological Studies of a Piperidinyl Appended Dipicolylamine Ligand and Its Rhenium Tricarbonyl Complex as Potential Therapeutic Agents for Human Breast Cancer

Bioinorganic Chemistry and Applications ◽

10.1155/2016/2675937 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Amali Subasinghe ◽

Inoka C. Perera ◽

Svetlana Pakhomova ◽

Theshini Perera

Keyword(s):

Breast Cancer ◽

Anticancer Agents ◽

Human Breast Cancer ◽

Human Breast ◽

Tricarbonyl Complex ◽

Nmr Spectrum ◽

H Nmr ◽

Biological Studies ◽

Visible Spectra ◽

Uv Visible

A novel ligand bearing a central piperidinyl sulfonamide group, N(SO2pip)dpa, and its corresponding Re tricarbonyl complex, [Re(CO)3(N(SO2pip)dpa)]+, have been synthesized in good yield. The methylene CH2signal seen as a singlet (4.54 ppm) in a1H NMR spectrum of the ligand in DMSO-d6appears as two doublets (5.39, 5.01 ppm) in a spectrum of the [Re(CO)3(N(SO2pip)dpa)]+complex and confirms the presence of magnetically nonequivalent protons upon coordination to Re. Structural results revealed that the Re–N bond lengths fall within the normal range establishing coordination of ligand to metal. The presence of intraligandπ→π⁎andn→π⁎transitions is indicated by the absorption peaks around 200–250 nm in UV-visible spectra. Absorption peaks in UV-visible spectra around 300 nm for metal complexes were identified as MLCT transitions. The S–N stretch observed as a strong peak at 923 cm−1for N(SO2pip)dpa appeared at a shorter frequency, at 830 cm−1in an FTIR spectrum of the [Re(CO)3(N(SO2pip)dpa)]+. The intense fluorescence displayed by the N(SO2pip)dpa ligand has quenched upon coordination to Re. Relatively low IC50values given by human breast cancer cells, MCF-7, (N(SO2pip)dpa = 139 μM, [Re(CO)3(N(SO2pip)dpa)]+= 360 μM) indicate that N(SO2pip)dpa and [Re(CO)3(N(SO2pip)dpa)]+are promising novel compounds that can be further investigated on their usage as potential anticancer agents.

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1-Norbornyl cation may be in equilibrium with 2-norbornyl cation

Progress in Reaction Kinetics and Mechanism ◽

10.1177/1468678319861319 ◽

2019 ◽

Vol 45 ◽

pp. 146867831986131

Author(s):

Andrew Mamantov

Keyword(s):

Nmr Spectrum ◽

Future Studies ◽

H Nmr ◽

C Nmr

New 1H and 13C NMR 400 MHZ spectra of the 2-Nb cation under stable ion conditions, for example, in SbF5/SO2F2/SO2ClF, −80 oC, show besides the usual 1H NMR resonances at δ 4.93, 2.82, 1.85, the never before seen singlet, δ 9.63, and doublet, δ 2.97 (J2,6 = 16.6 Hz), ratio 1.00 : 1.07, proposed to be due to resonance-stabilized bridgehead 1-Nb cationic enantiomers in equilibrium with 2-Nb cation. The corresponding 13C proton-coupled NMR spectrum, −80 oC, has a C3,5,7 triplet, δ 30.45, J(CH) = 139.14 Hz, and C4 doublet, δ 37.7, J(CH) = 154.54 Hz. The C1,2,6 absorption, δ 91.04 is relatively broad, whereas previously, at −70 oC, it was a pentuplet. The 13C proton-decoupled spectrum at −80 oC shows the C4 doublet and C3,5,7 triplet collapsed to a singlet, but the C1,2,6 resonance is still broad. Analyses support the slowing exchange between resonance stabilized enantiomeric 2-cations at ≤ –159 oC. Some future studies are proposed.

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Synthesis of Newer Mercury(II) Complexes of Meso-Tetraaryl-21,23-Dithiaporphyrins

Advanced Science Engineering and Medicine ◽

10.1166/asem.2020.2539 ◽

2020 ◽

Vol 12 (3) ◽

pp. 416-421

Author(s):

Soumee Bhattacharya ◽

Uma Narang ◽

Kumar Karitkey Yadav ◽

Anshu Dandia ◽

Shive M. S. Chauhan

Keyword(s):

Fluorescence Spectra ◽

Mercuric Acetate ◽

H Nmr ◽

Sensing Applications ◽

Mercury Complex ◽

Mercury Complexes ◽

Visible Spectra ◽

Uv Visible ◽

Chloroform Methanol ◽

C Nmr

Due to the larger size of hetero atom and poor binding with metals, N2X2 type of core modified porphyrins show lesser tendency to form metal complexes. Mercury(II) complexes of symmetrical and unsymmetrical meso-tetraaryl-21,23-dithiaporphyrins are synthesized and characterized by the reaction of corresponding meso-tetraaryl-21,23-dithiaporphyrins with mercuric acetate in chloroform/methanol. These mercury complexes are well characterized by their UV-Visible spectra, fluorescence spectra, 1H NMR, 13C NMR and elemental analysis. Soret bands of mercury complex of unsymmetrical 5,20-bis-(4′-methoxyphenyl)-10,15-bisphenyl-21,23-dithiaporphyrin appeared at 442 nm and 462 nm whereas Q band appeared at 516 nm, 560 nm, 620 nm and 714 nm. Appearance of four Q bands is characteristic for this mercury complex of N2X2 type of core modified porphyrins. Mercury complex of unsymmetrical 5,20-bis-(4′-methoxyphenyl)-10,15-bisphenyl-21,23dithiaporphyrin is an excellent fluorescent molecule and showed fluorescence spectrum at 722 nm. These core modified porphyrin complexes provides a good coordination examples of mercury complexes of 21,23-dithiaporphyrins that can be used in sensing applications.

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Antimicrobial Applications of Transition Metal Complexes of Benzothiazole Based Terpolymer: Synthesis, Characterization, and Effect on Bacterial and Fungal Strains

Bioinorganic Chemistry and Applications ◽

10.1155/2014/764085 ◽

2014 ◽

Vol 2014 ◽

pp. 1-16 ◽

Cited By ~ 10

Author(s):

Mohamed A. Riswan Ahamed ◽

Raja S. Azarudeen ◽

N. Mujafar Kani

Keyword(s):

Metal Complexes ◽

Elemental Analysis ◽

Biological Activities ◽

Gel Permeation Chromatography ◽

Spectral Studies ◽

X Ray Diffraction ◽

Spectral Techniques ◽

H Nmr ◽

Uv Visible ◽

C Nmr

Terpolymer of 2-amino-6-nitro-benzothiazole-ethylenediamine-formaldehyde (BEF) has been synthesized and characterized by elemental analysis and various spectral techniques like FTIR, UV-Visible, and1H and13C-NMR. The terpolymer metal complexes were prepared with Cu2+, Ni2+, and Zn2+metal ions using BEF terpolymer as a ligand. The complexes have been characterized by elemental analysis and IR, UV-Visible, ESR,1H-NMR, and13C-NMR spectral studies. Gel permeation chromatography was used to determine the molecular weight of the ligand. The surface features and crystalline behavior of the ligand and its complexes were analyzed by scanning electron microscope and X-ray diffraction methods. Thermogravimetric analysis was used to analyze the thermal stability of the ligand and its metal complexes. Kinetic parameters such as activation energy(Ea)and order of reaction (n) and thermodynamic parameters, namely,ΔS,ΔF,S*, andZ, were calculated using Freeman-Carroll (FC), Sharp-Wentworth (SW), and Phadnis-Deshpande (PD) methods. Thermal degradation model of the terpolymer and its metal complexes was also proposed using PD method. Biological activities of the ligand and its complexes were tested againstShigella sonnei,Escherichia coli,Klebsiellaspecies,Staphylococcus aureus,Bacillus subtilis, andSalmonella typhimuriumbacteria andAspergillus flavus,Aspergillus niger,Penicilliumspecies,Candida albicans,Cryptococcus neoformans,Mucor speciesfungi.

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Bis-indole substituted phthalocyanines: Photophysical and photochemical properties

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424620500522 ◽

2020 ◽

Vol 25 (01) ◽

pp. 66-74

Author(s):

Kevser Harmandar ◽

Esra N. Kaya ◽

Mehmet F. Saglam ◽

Ibrahim F. Sengul ◽

Devrim Atilla

Keyword(s):

Photodynamic Therapy ◽

Singlet Oxygen ◽

Spectral Data ◽

Quantum Yields ◽

Oxygen Generation ◽

Fluorescence Quantum Yields ◽

H Nmr ◽

Singlet Oxygen Generation ◽

Photochemical Properties ◽

C Nmr

Tetra substituted peripheral and non-peripheral Zn(II) phthalocyanines were successfully synthesized employing 4-(bis(3-methyl-1H-indol-2-yl)methyl)phenol as a starting material. The structure of these synthesized compounds was confirmed using 1H NMR, [Formula: see text]C NMR, infrared (IR), UV-vis, and MALDI-TOF spectral data. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation) properties of all synthesized peripheral and non-peripheral compounds were investigated in order to determine the potential of these compounds for application in photodynamic therapy.

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Synthesis and characterization of silver(I) complexes of thioureas and thiocyanate: crystal structure of polymeric (1,3-diazinane-2-thione)thiocyanato silver(I)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2014-0263 ◽

2015 ◽

Vol 70 (8) ◽

pp. 541-546 ◽

Cited By ~ 5

Author(s):

Muhammad Nawaz Tahir ◽

Anvarhusein A. Isab ◽

Fozia Afzal ◽

Kashif Raza ◽

Shah Muhammad ◽

...

Keyword(s):

Crystal Structure ◽

Nmr Spectrum ◽

Coordination Environment ◽

X Ray Crystallography ◽

H Nmr ◽

Ir And Nmr Spectroscopy ◽

A Chain ◽

Distorted Tetrahedral Coordination ◽

C Nmr

AbstractSilver(I) complexes of thioureas and thiocyanate, [(Tu)AgSCN], [(Metu)AgSCN], [(Dmtu)AgSCN], [(Tmtu)(AgSCN)1.5], [(Imt)AgSCN], and [(Diaz)AgSCN] (where Tu = thiourea, Metu = N-methylthiourea, Dmtu = N,N′-dimethylthiourea, Tmtu = N,N,N′,N′-tetramethylthiourea, Imt = 1,3-imidazolidine-2-thione, and Diaz = 1,3-diazinane-2-thione), have been prepared and characterized by elemental analysis, IR and NMR spectroscopy, and thermal analysis. The crystal structure of one of them, [(Diaz)Ag(SCN)] (1), was determined by X-ray crystallography. The crystal structure of 1 shows that the complex exists in the form of a chain-like polymer comprising [Ag(μ2-Diaz)(μ2-SCN)] units. The silver atoms are bridged by μ2-thione sulfur atoms of Diaz and μ2-thiocyanate sulfur atoms. Thereby each silver atom adopts a distorted tetrahedral coordination environment comprising four sulfur atoms, two from thione and two from thiocyanate ligands. An upfield shift in the >C=S resonance of thiones in 13C NMR and a downfield shift in the N–H resonance in 1H NMR are consistent with the sulfur coordination to silver(I). The appearance of a band around 2100 cm–1 in the IR and a resonance around 125 ppm in the 13C NMR spectrum indicates the binding of thiocyanate to silver(I).

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Synthesis and Antibacterial Activity of Some Derivatives of 2-Methylbenzimidazole Containing 1,3,4-Oxadiazole or 1,2,4-Triazole Heterocycle

Journal of Chemistry ◽

10.1155/2016/1507049 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Cong Nguyen Tien ◽

Duc Tran Thi Cam ◽

Ha Bui Manh ◽

Dat Nguyen Dang

Keyword(s):

Antimicrobial Activity ◽

Antibacterial Activity ◽

Spectral Data ◽

H Nmr ◽

Mold And Yeast ◽

Derivatives Of ◽

C Nmr

5-[(2-Methyl-1H-benzimidazol-1-yl)methyl]-1,3,4-oxadiazole-2-thiol or 5-[(2-methyl-1H-benzimidazol-1-yl)methyl]-4-(4-methylphenyl)-1,2,4-triazol-3-thiol which were prepared starting from 2-methylbenzimidazole in the reaction with appropriateN-aryl-2-chloroacetamides afforded two series ofN-aryl-2-{5-[(2-methyl-1H-benzimidazol-1-yl)methyl]-1,3,4-oxadiazol-2-yl}sulfanylacetamides andN-aryl-2-{5-[(2-methyl-1H-benzimidazol-1-yl)methyl]-4-(4-methylphenyl)-4H-1,2,4-triazol-3-ylthio}acetamides, respectively. The structures of the compounds were elucidated on the basis of IR, MS,1H-NMR, and13C-NMR spectral data. The compounds containing 1,3,4-oxadiazole or 1,2,4-triazole heterocycle also were tested for their antimicrobial activity against bacteria, mold, and yeast.

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