共查询到20条相似文献,搜索用时 15 毫秒
1.
Prithwiraj Byabartta 《Transition Metal Chemistry》2007,32(8):1007-1011
Reaction of [Au(C6F5)(tht)2Cl](OTf) with RaaiR′ in CH2Cl2 medium leads to [Au(C6F5)(RaaiR′)Cl](OTf) [RaaiR′ = p-R–C6H4–N=N–C3H2–NN-1-R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3
(2), CH2Ph (3), tht is tetrahydrothiophen]. The maximum molecular peak of [Au(C6F5)(MeaaiMe)Cl] is observed at m/z 599.51 (100 %) in the FAB mass spectrum. Ir spectra of the complexes show –C=N– and –N=N– stretching near at 1590 and 1370 cm−1 and near at 1510, 955, 800 cm−1 due to the presence of pentafluorophenyl ring. The 1H-NMR spectral measurements suggest methylene, –CH2–, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph shows AB type quartets. 13C-NMR spectrum of complexes confirm the molecular skeleton. In the 1H-1H-COSY spectrum as well as contour peaks in the 1H-13C HMQC spectrum for the present complexes, assign the solution structure and stereoretentive conformation. The electrochemistry
gives the ligand reduction peaks. 相似文献
2.
The reaction of [Au(OSO2CF3)(PPh3)] with arylazoimidazole in dichloromethane followed by NH4PF6 leads to [Au(RAaiR′)(PPh3)]PF6 (RAaiR′ = p-R-N=N-C3H2-NN-1-R′), abbreviated as N,N′/-chelator, where N (imidazole) and N (azo) represent N and N′, respectively; R = H (a), Me
(b), Cl (c), and R′ = Me (I), CH2CH3 (II), CH2Ph (III)]. IR spectra of the complexes show -C=H- and -N=N-stretchings at 1590 and 1370 and at 1100, 755, 695, 545, and 505
cm−1 due to the presence of the triphenylphosphine ring. The 1H NMR spectral measurements suggest that methylene (-CH2-) in (RAai)Et gives a complex of the AB type multiplet with a coupling constant of ∼7.6 Hz while in RAaiCH2Ph it shows AB type quartets with coupling constant of av. 7.2 Hz. Considering the arylazoimidazole moity, there are different
carbon atoms in the molecule giving different peaks in the 13C NMR spectrum of the complexes. In the 1H-1H COSY spectrum of the present complexes, the absence of any off-diagonal peaks extending from δ = 14.12 and 9.55 ppm confirms
their assignment of no proton on N(1) and N(3), respectively. Contour peaks in the 1H-13C HMQC spectrum in the present complexes, the absence of any contours at δ = 157.12, 160.76, 155.67, and 157.68–160.2 ppm
assign them to the C(2), C(6), C(12), and C(PPh3) carbon atoms, respectively. The solution structure and stereoretentive transformation in each step have been established
from the 1H NMR results.
The article was submitted by the authors in English. 相似文献
3.
Reaction of [AuIII(C6F5)3(tht)] with RaaiR′ in dichloromethane medium leads to [AuIII(C6F5)3 (RaaiR′)] [RaaiR′=p-R-C6H4-N=N-C3H2-NN-l-R′, (1-3), R = H (a), Me (b), Cl (c) and R′= Me (1), CH2CH3 (2), CH2Ph (3), tht is tetrahydrothiophen]. The nine new complexes are characterised by ES/MS as well as FAB, IR and multinuclear NMR (1H,13C,19F) spectroscopic studies. In addition to dimensional NMR studies as1H,1H COSY and1H13C HMQC permit complete assignment of the complexes in the solution phase. 相似文献
4.
P. Byabartta 《Russian Journal of Coordination Chemistry》2009,35(4):253-258
Reaction of [Au(C6F5)(PPh3)(OSO2CF3)2] with RaaiR′ in dichloromethane medium followed ligand addition leads to [Au(PPh3)(C6F5)(RaaiR′)](OSO2CF3)2 where RaaiR′ = p-R-C6H4-N=N-C3H2-NN-1-R′ (I–III), abbreviated as N, N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a),
Me (b), Cl (c) and R′ = Me (I), CH2CH3 (II), CH2Ph (III), PPh3 is triphenylphosphine, OSO2CF3 is the triflate anion. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. IR
spectra of the complexes show -C=N- and -N=N- stretching near at ∼1590 and 1370 cm−1 and at ∼1100, 755, 695, 545, and 505 cm−1 due to the presence of triphenylphosphine and pentafluoropheny ring. The 1H NMR spectral measurements suggest methylene (-CH2-) in RaaiEt that gives a complex AB type multiplet with coupling constant of av. 6.6 Hz while in RaaiCH2Ph it shows AB type quartets with coupling constant of av. 6.2 Hz. Considering all the moitie there are a lot of different
carbon atoms in the molecule which gives a lot of eleven different peaks in the 13C {1H}NMR spectrum. In the 1H-1H COSY NMR spectrum of the present complexes and contour peaks in the 1H-13C HMQC NMR spectrum in the present complexes, assign the solution structure and stereo-retentive transformation in each step.
The article is published in the original. 相似文献
5.
Reaction of [Ni(dppe)Cl2/Br2] with AgOTf in CH2Cl2 medium following ligand addition leads to [Ni(dppe)(OSO2CF3)2] and then [Ni(dppe)(RaaiR)](OSO2CF3)2 [RaaiR′ = p–R–C6H4–N=N–C3H2–NN-1–R′,(1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3
(2), CH2Ph (3), OSO2CF3 is the triflate anion]. 31P{1H}-NMR confirm that stable bis-chelated square planar Ni(II) azoimine–dppe complex formation with one sharp peaks. The 1H NMR spectral measurements suggest azoimine link is present with lot of phenyl protons in the aromatic region. Considering
all the moities there are a lot of different carbon atoms in the molecule which gives many different peaks in the 13C(1H)-NMR spectrum. In the 1H-1H COSY spectrum in the present complexes and contour peaks in the 1H-13C-HMQC spectrum in the present complexes, assign the solution structure and stereoretentive conformation in each complexes. 相似文献
6.
Seikh Jasimuddin 《Transition Metal Chemistry》2006,31(6):724-729
Dechlorination of M(RaaiR′)
n
Cl2 by AgNO3 produced [M(RaaiR′)
n
(MeCN)2]+2 [M = Ru(II), n = 2; Pt(II), n = 1; RaaiR′ = 1-alkyl-2-(arylazo)imidazole)] which upon reaction with the nucleobase cytosine (C) in MeCN solution gave cytosinato
bridged dimeric compounds which were isolated as perchlorate salts [M2(RaaiR′)
n
(C)2](ClO4)2 · H2O. The products were characterized by IR, u.v.–vis., 1H-n.m.r. spectroscopy and cyclic voltammetry. In MeCN solution the ruthenium complexes exhibit a strong MLCT band at 550–555 nm
and two redox couples positive to SCE due to two metal-center oxidation along with ligand reduction, negative to SCE. The
platinum complexes show a weak transition at 500–520 nm in MeCN and exhibit only ligand reduction in cyclic voltammetry. The
coordination of the ligand was supported by 1H-n.m.r. spectral data. 相似文献
7.
P. Byabartta 《Russian Journal of Coordination Chemistry》2009,35(7):482-485
Aromatic ring amination reactions in the ruthenium complex of 1-methyl-2-(phenylazo)imidazole is described. The substitutionally
inert cationic brown complex [Ru(HAaiMe)3](ClO4)2(I) reacts smoothly with aromatic amines neat and in the presence of air produce cationic and intense blue complexes [Ru(ArNH-AaiMe)3](ClO4)2 (II) (ArNH-AaiMe = 1-methyl-2-[(4-(arylamino)phenyl)azo] imidazole, Ar = C6H5 (IIa), p-C6H4Me (IIb)). These were purified on a preparative TLC plate (large plates of thin layer chromatography). The results are compared
with those of the starting complex, [Ru(HAaiMe)3](ClO4)2 (I). The transformation I → II involves aromatic ring amination at the para carbon (with respect to the diazo function) of the pendant phenyl rings of all three coordinated azoimine ligands in I. The ruthenium complex II is characterized by intense blue solution color. The lowest energy transitions in these complexes appear near 600 nm, which
have been attributed to intraligand charge-transfer transitions. IR spectra of the complexes show -C=N- and -N=N- stretching
at 1590 and 1370 cm−1 which is red shifted by 40 and 90 cm−1 from the free ligand value and supports Ru-azo nitrogen π bonding interection. The 1H NMR spectral measurements suggest methyl and aromatic ring protons. Considering three arylazoimidazole moities there are
forty eight different carbon atoms in the molecule which gives a total of that different peaks in the 13C (1H) NMR spectrum. In the 1H-1H COSY spectrum of the present complex, absence of any off-diagonal peaks extending from δ = 14.12 and 9.55 ppm confirms their
assignment of no proton on N(1) and N(3), respectively. Contour peaks in the 1H-13C HMQC spectrum in the present complex assign them hydrogen carbon atoms relationship, respectively. The electrons are believed
to be added successively to the three azo functions.
The article is published in the original. 相似文献
8.
Prithwiraj Byabartta 《Russian Journal of General Chemistry》2009,79(6):1214-1217
The reaction of [Ni(dppa)(Cl)2] or [Ni(dppa)(Br)2] with AgOTf gives [Ni(dppa)(OTf)2], which then form [Ni(dppa)(RaaiR)](OSO2CF3)2 under the action of arylazoimidazole(RaaiR) in a dichloromethane medium [RaaiR′ = p-R-C6H4-N=N-C3H2-NN-1-R′, (I–III), abbreviated as N,N′-chelating agent, where N(imidazole) and N(azo) represent N and N’, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (I), CH2CH3 (II), CH2Ph (III), OSO2CF3 is the triflate anion]. The 1H NMR spectral measurements suggest that a bound azoimine is responsible for a number of signals of phenyl protons in the
aromatic region. The molecules of the complexes contain a number of different carbon atoms which gives a number of different
peaks in the 13C (1H) NMR spectrum. The text was submitted by the author in English.
The text was submitted by the author in English. 相似文献
9.
Prithwiraj Byabartta 《Russian Journal of Inorganic Chemistry》2010,55(7):1052-1056
Reaction of [Pd(dppe)Cl2/Br2] with AgOTf in a dichloromethane medium followed by ligand addition led to [Pd(dppe)(OSO2CF3)2] and then [Pd(dppe)(RaaiR)](OSO2CF3)2 [RaaiR′ = p-R-C6H4-N=N-C3H2-NN-1-R′, (1–3), abbreviated as a N,N′-chelator, where N(imidazole) and N(azo) are represented by N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3 (2), CH2Ph (3), OSO2CF3 is the triflate anion, dppe = 1,2-bis-(diphenylphosphinoethane)]. 31P “1H” NMR confirmed that due to the two phosphorus atom interaction in the azoimine symmetrical environment one sharp peak was
formed. The 1H NMR spectral measurements suggest that azo-imine link with lot of phenyl protons in the aromatic region. 13C (1H) NMR spectrum, 1H, 1H COSY and 1H, 13C HMQC spectrum assign the solution structure and stereo-retentive conformation in each complex. 相似文献
10.
Iron (II) complexes of 1-alkyl-2-(arylazo)imidazoles (p-R-C6H4-N=N-C3H2NN-1-R′, R = H (a), Me (b), Cl (c) and R′ = Me (1/3), Et (2/4) have been synthesized and formulated astris-chelates Fe(RaaiR′)
3
2+
. They are characterized by microanalytical, conductance, UV-Vis, IR, magnetic (polycrystalline state) data. The complexes
are low spin in character,t
2g
6
(Fe(II)) configurations. 相似文献
11.
Reaction of [Au2(dppm)Cl2] with AgOTf in CH2Cl2 medium followed ligand addition and leads to [Au2(dppm)(RaaiR′)](OTf) [RaaiR′ = p-R–C6H4–N = N–C3H2–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3
(2), CH2Ph (3), OSO2CF3 is the triflate anion, and dppm is the diphenylphosphinomethane-ring]. The 1H-n.m.r. spectral measurements suggest methylene, –CH2–, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph it shows AB type quartets with coupling constant of avg. 6 Hz. Considering all the moities there are a lot of different
carbon atoms in the molecule which gives a lot of different peaks in the 13C-n.m.r spectrum. In the 1H–1H-COSY spectrum of the present complexes and contour peaks in the 1H–13C-HMQC spectrum in the present complexes, assign the solution structure and stereoretentive transformation in each step. 相似文献
12.
Prithwiraj Byabartta 《Transition Metal Chemistry》2005,30(7):804-813
Ag+ assisted aquation of blue cis-trans-cis-RuCl2(RaaiR′)2 (4–6) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH2)2(RaaiR′)2](ClO4)2 [Raai R′=p-R-C6H4
N=N–C3H2–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), OMe (b), NO2 (c) and R′ = Me (1/4/7/10), CH2CH3 (2/5/8/11), CH2Ph (3/6/9/12)] that have been reacted with NO2−in warm EtOH resulting in violet dinitro complexes of the type, Ru(NO2)2(RaaiR′)2 (7–9). The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the compounds, (7b–9b) with conc. HClO4 nitro-nitrosyl derivatives, [Ru(NO2)(NO)(OMeaaiR′)2](ClO4)2 (10b–12b) are isolated. The solution structure and stereoretentive transformation in each step have been established from 1H n.m.r. results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display
one metal-centred oxidation and successive ligand-based reductions. The redox potentials of Ru(III)/Ru(II) (E1/2M) of (10b–12b) are anodically shifted by ∼
∼0.2 V as compared to those of dinitro precursors, (7b–9b). The ν(NO) >1900 cm−1 strongly suggests the presence of linear Ru–NO bonding. The electrophilic behaviour of metal bound nitrosyl has been proved
in one case (12b) by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active methine
group, and the heteroleptic tris chelates thus formed have been characterised. 相似文献
13.
P. Byabartta 《Russian Journal of Coordination Chemistry》2009,35(8):582-587
The hetero-tris-chelates of the formula [Ru(Phen)(RAaiR′)2](ClO4)2 (Phen = 1,10-phenanthroline, RAaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N=N-C3H2-NN-1-R′, where R = H (a), Me (b), Cl (c) and R′ = Me (II), Et (III), CH2Ph (IV)) have been isolated from the reaction of ctc-[RuCl2(RAaiR′)2] with AgNO3 + Phen or [Ag(Phen)2](ClO4) in acetone at 40°C in dark followed by the addition of NaClO4 (aq). The stereo-chemistry of the complexes have been supported by 1H NMR data. Considering the arylazoimidazole and phenanthroline moietie there are twenty different carbon atoms in the molecule
which gives a total of twenty different peaks in the 13C NMR spectrum of complex Ia. Cyclic voltammograms show Ru(III)/Ru(II) couple at 1.3–1.4 V vs SCE along with three successive ligand reductions.
The article is published in the original. 相似文献
14.
Prithwiraj Byabartta 《Transition Metal Chemistry》2005,30(8):978-986
The reaction of ctc-[Ru(RaaiR′)2Cl2] (3a–3i) [RaaiR′=1-alkyl-2-(arylazo)imidazole, p-R—C6H4—N=N— C3H2NN(1)—R′, R=H, OMe, NO2, R′=Me, Et, Bz] with KS2COR′′ (R′′=Me, Et, Pr, Bu or CH2Ph) in boiling dimethylformamide afforded [RuII{o-S—C6H4(p-R-)—N=N—C3H2NN(1)—R′}2] (4a–4i), where the ortho-carbon atom of the pendant phenyl ring of both ligands has been selectively and directedly thiolated. The newly formed tridentate
thiolate ligands are bound in a meridional fashion. The solution electronic spectra exhibit a strong MLCT band near 700 nm
and near 550 nm, respectively in DCM. The molecular geometry of the complexes in solution has been determined by H n.m.r.
spectroscopy. Cyclic voltammograms show a Ru(II)/Ru(III) couple near 0.4 V and an irreversible oxidation response near 1.0
V due to oxidation of the coordinated thiol group, along with two successive reversible ligand reductions in the range −0.80–0.87
V (one electron), −1.38–1.42 V (one electron). Coulometric oxidation of the complexes at 0.6 V versus SCE in CH2Cl2 produced an unstable Ru(III) congener. When R=Me the presence of trivalent ruthenium was proved by a rhombic e.p.r. spectrum
having g1=2.349, g2=2.310. 相似文献
15.
Prithwiraj Byabartta 《Transition Metal Chemistry》2007,32(3):304-313
Reaction of [Au(PPh3)2(tht)2](OSO2CF3)3 with RaaiR′ in CH2Cl2 medium following ligand addition leads to [Au(PPh3)2(RaaiR′)](OTf)3 [RaaiR′ = p-R–C6H4–N=N–C3H2–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3
(2), CH2Ph (3), PPh3 is triphenylphosphine, OSO2CF3 is the triflate anion, tht is tetrahydrothiophen]. The maximum molecular peak of the corresponding molecule is observed in
the ESI mass spectrum. The 1H-nmr spectral measurements suggest methylene, –CH2–, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph it shows AB type quartets. 13C-nmr spectrum suggests the molecular skeleton. In the 1H–1H COSY spectrum as well as contour peaks in the 1H–13C heteronuclear multiple-quantum coherence (HMQC) spectrum assign the solution structure. Electrochemistry assign ligand reduction
part rather than metal oxidation. 相似文献
16.
Nucleophilic substitution of Pd(RaaiR′)Cl2 [(RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C6H4-N=N-C3H2NN-1-R′; where R = H(a)/ Me(b)/ Cl(c) and R′ = Et(1)/Bz(2)] with 2-Mercaptopyridine (2-SH-Py) in acetonitrile (MeCN) at 298 K, to form [Pd2(2-S-Py)4], has been studied spectrophotometrically under pseudo-first-order conditions and the analyses support the nucleophilic association
path. The reaction follows the rate law, Rate = {k
0 + k [2-SH-Py]
0
2
}[Pd(RaaiR′)Cl2]: first order in Pd(RaaiR′)Cl2 and second order in 2-SH-Py. The rate of the reaction follows the order: Pd(RaaiEt)Cl2
(1) < Pd(RaaiBz)Cl2
(2) and Pd(MeaaiR′)Cl2 (b) < Pd(HaaiR′)Cl2 (a) < Pd(ClaaiR′)Cl2 (c). External addition of Cl− (LiCl) and HCl suppresses the rate (Rate ∝ 1/[Cl−]0 & ∝1/[HCl]0). The reactions have been studied at different temperatures (293–308 K) and activation parameters (Δ‡ H° and Δ ‡ S°) of the reactions were calculated from the Eyring plot and support the proposed mechanism. 相似文献
17.
Two polypyridyl ligands, 5-(4′-ethynylbenzo-15-crown-5)-2,2′-bipyridine (L1) and 3-bromo-8-(4′-ethynylbenzo-15-crown-5)-1,10-phenanthroline (L2), and their Ru(II) complexes [(bpy)2RuL](PF6)2 have been prepared and characterized. Both complexes exhibit metal-to-ligand charge transfer absorption at around 452 nm
and emission at around 640 nm in MeCN solution. Electrochemical studies of the complexes reveal a Ru(II)-centered oxidation
at around 1.31 V and three ligand-centered reductions. The binding ability of the complexes with Na+ has been investigated by UV/Vis absorption, emission, and electrochemical titrations. Addition of Na+ to MeCN solutions of both complexes results in a progressive enhancement of the emission, a red-shift of the UV/Vis absorption,
and a progressive cathodic shift of the Ru(II)-centered E
1/2 couple. The stability constants for the 1:1 stoichiometry adducts of the complexes with Na+ have been obtained from the UV/Vis absorption titrations. 相似文献
18.
Prithwiraj Byabartta 《Transition Metal Chemistry》2007,32(3):314-324
Silver assisted de-bromination gives [Au2(dppm/dppe/dppa) (OTf)2], which on reaction with 4,4′-bpy and gold(I) phosphines in CH2Cl2 medium, by the self assembly technique, leads to [(PPh3)Au(4,4′-bpy)Au(PPh3)], (1a–1d,2), [{Au2(dppm/dppe/dppa)}{(4,4-bpy)Au(PPh3)}2](NO3)4, (3), [{Au4(dppm/dppe/dppa)2(4,4-bpy)2}](OTf)4,
(4), [{(PPh3)AuI(4,4′-bpy)}2AuIII(C6F5/Mes)](NO3)3, (5) [dppm/dppe/dppa =diphenyl phosphino-methane(a), –ethane(b), ammine(c), C6F5/Mes pentafluorophenyl/mesitylene]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum.
Ir spectra of the complexes show –C=C–, –C=N–, as well as phosphine, mesitylene and pentafluorophenyl stretching. The 1H-NMR spectra as well as 31P(1H)-NMR suggest solution stereochemistry, proton movement and phosphorus proton interaction. Considering all the moities there
are a lot of carbon atoms in the molecule reflected by the 13C(H)-NMR spectrum. In the 1H–1H COSY spectrum of the present complexes and contour peaks in the 1H–13C-HMQC spectrum, assign the solution structure and stereoretentive transformation in each step. 相似文献
19.
P. Byabartta 《Russian Journal of Coordination Chemistry》2008,34(3):220-224
Tris-chelate complex [Ru(Pap)(RAaiR′)2](ClO4)2 (I, II, III/a, b, c) (where RAaiR′ = 1-alkyl-(2-arylazo)imidazole, R = H, Me, Cl (a, b, c); R′ = Me, Et, CH2Ph (I, II, III), and Pap = phenylazopyridine) was prepared by silver assisted synthetic route. IR spectra of the complexes
support Ru-azo nitrogen π-bonding interaction. 1H NMR spectra suggest that there are two types of streochemical orientation of RAaiR′ around ruthenium(II). Cyclic voltammetry
of the complexes shows one metal oxidation Ru(II)/Ru(III) at 1.4–1.5 V and three successive ligand reduction couples at the
negative side of the reference potential in the range from −0.5 to −0.56, −0.7 to −0.8, and from −1.25 to −1.40 V, respectively.
The text was submitted by the author in English. 相似文献
20.
Three Ru(II) complexes, namely [Ru(bipy)2PRIP]2+ (1), [Ru(dmb)2PRIP]2+ (2), and [Ru(phen)2PRIP]2+ (3) (dmb = 4,4′-dimethyl-2,2′-bipyridine; PRIP = 2-(pyrrole) imidazo [4,5-f]-1,10-phenanthroline) have been synthesized and
characterized by elemental analysis, mass spectra, IR, 1H NMR and 13C NMR. The DNA-binding properties of the three complexes with calf-thymus DNA (CT-DNA) were investigated by spectrophotometry,
fluorescence methods and viscosity measurements. The results suggest that all three complexes bind to CT-DNA through intercalation.
Also, when irradiated at 365 nm, the three complexes promote the photocleavage of plasmid pBR-322 DNA. Under comparable experimental
conditions, complex 3 cleaves DNA more effectively than complexes 1 and 2. 相似文献