The First Butyltin(IV) Homo- and Heterobimetallic Diethanolaminates

Equimolar reactions of BuSn(OPrⁱ)₃ with diethanolamines, RN(CH₂CH₂ OH) ₂ (abbreviated as RdeaH₂, where R = H or Me), afford dimeric isopropoxo-bridged six-coordinate butyltin(IV) complexes [{Bu(η³-Rdea)Sn(μ-OPrⁱ)}₂] (R = H ( 1 ), Me ( 2 )). Interactions between BuSn(OPrⁱ)₃ and diethanolamines (RdeaH₂) in a 1:2 molar ratio yield monomeric derivatives of the type [BuSn(Rdea)(RdeaH)] (R = H ( 3 ), R = Me ( 4 )). These homometallic complexes on 1:1 reactions with an appropriate metal alkoxide form monomeric heterobimetallic complexes of the type [BuSn (Rdea)₂ {M(OR′)_n}] (R = H, M = Al, R′ = Prⁱ, n = 2 ( 5 ); R = H, M = Ti, R = Prⁱ, n = 3 ( 6 ); R = H, M = Zr, R′ = Prⁱ, n = 3 ( 7 ); R = Me, M = Al, R′ = Prⁱ, n = 2 ( 8 ); R = Me, M = Ti, R′ = Prⁱ, n = 3 ( 9 ); R = Me, M = Ge, R′ = Et, n = 3 ( 10 )). The driving force behind this work was (i) to explore the utility of homometal complexes ( 1 ) –( 4 ) in assembling a metal alkoxide fragment via a condensation reaction and (ii) to gain insights into the structures of new compounds by NMR spectral data. All of these derivatives have been characterized by elemental analysis, spectroscopic (IR, NMR; ¹H, ²⁷Al, and ¹¹⁹Sn) studies, and molecular weight measurements. ¹¹⁹Sn NMR spectral studies indicate that both the homometallic ( 3 ) and ( 4 ) and heterobimetallic ( 5 ) – ( 9 ) complexes exist in a solution in an equilibrium of six- and five-coordinated tin(IV) species.     

三个二(有机锡)吡啶-2,3(5)-二甲酸酯的合成、结构和体外抗癌活性

在微波溶剂热中,三环已基氢氧化锡、氧化双(三((2-甲基-2-苯基)丙基)锡)与吡啶-2,3(5)-二甲酸反应,合成了3个双核二(有机锡)吡啶-2,3(5)-二甲酸酯:Py(CO)_2(SnR_3)_2(MeOH)_n(R:Cy,n=1(1),2(2);R:PhCMe_2CH_2,n=0(3)),对它们的组成和结构进行了元素分析、IR、(~1H,~(13)C,~(119)Sn)NMR和X射线晶体衍射分析表征,化合物中心锡与配基原子构成畸形四/六面体构型,由于氢键作用,化合物1形成一维链,2形成二维34元大环网状结构。化合物对人结肠癌(HT-29)、肝癌细胞(HepG2)、乳腺癌(MCF-7)、鼻咽癌(KB)和肺癌细胞(A549)的增殖有较强的抑制作用。     

Spectroscopic characterization and <Emphasis Type="Italic">Ab initio</Emphasis> calculations of new diazaphosphole and diazaphosphorinane

Phosphoryl chloride is used as a starting material to synthesize new diazaphosphole, (1) and diazaphosphorinane, (2). The products are characterized by ¹H, ¹³C, ³¹P NMR, and IR spectroscopy. A high value ² J(PNH) = 17.0 Hz, 17.2 Hz is measured for two non-equivalent NH protons of endocyclic nitrogen atoms in compound 1, while it greatly decreases to 4.5 Hz in 2. Also, great amounts are obtained for two ² J(P,C) as well as two ³ J(P,C) in the ¹³C NMR spectrum of 1, but they are zero in 2. Here, the effect of ring strain and ring size on the structural and spectroscopic parameters is observed. The ³¹P NMR spectra reveal that δ(³¹P) of compound 1 is far much more downfield (12.63 ppm) relative to that of compound 2 (−10.39 ppm). Furthermore, ab initio quantum chemical calculations are performed to optimize the structures of these molecules by density functional theory (B3LYP) and Hartree-Fock (HF) methods, using the standard 6−31+G** basis set. The stabilization energies are calculated by the equation ΔE _{stabilization} = E _molecule − ΣE _i , where i = atom. To obtain the atomic hybridizations, NBO computations are made at the B3LYP/6−31+G** level. Also, by NMR calculations the ¹H, ¹³C, ³¹P chemical shifts are obtained and compared with the experimental ones.     

三个二（有机锡）吡啶-2,3（5）-二甲酸酯的合成、结构和体外抗癌活性

在微波溶剂热中,三环已基氢氧化锡、氧化双（三（（2-甲基-2-苯基）丙基）锡）与吡啶-2,3（5）-二甲酸反应,合成了3个双核二（有机锡）吡啶-2,3（5）-二甲酸酯：Py（CO）₂（SnR₃）₂（MeOH） _n（R：Cy,n=1（1）,2（2）;R：PhCMe₂CH₂,n=0（3））,对它们的组成和结构进行了元素分析、IR、（¹H,¹³C,¹¹⁹Sn） NMR和X射线晶体衍射分析表征,化合物中心锡与配基原子构成畸形四/六面体构型,由于氢键作用,化合物1形成一维链,2形成二维34元大环网状结构。化合物对人结肠癌（HT-29）、肝癌细胞（HepG2）、乳腺癌（MCF-7）、鼻咽癌（KB）和肺癌细胞（A549）的增殖有较强的抑制作用。     

The structure of angustifoline,an alkaloid ofLupinus angustifolius,in solution

Summary The¹H and¹³C NMR spectra of the lupin alkaloidangustifoline 1 in four solvents (cyclohexane-d₁₂, CDCl₃, CD₃CN, and C₆D₆) were assigned using 2D H,H and H,C COSY and 2D J-resolved spectra. The torsional HCCH angles calculated from the vicinalJ _HH coupling constants are essentially in agreement with those expected for the deformed all-chair conformation withendo oriented N(12)-H bond, reported earlier for1 in the solid state. Some arguments seem to point, however, to a small contribution of other conformations: with ring A deformed in another direction, deformed all-chair withexo oriented N(12)-H bond and/or a conformation with ring C in the boat form.Lupin Alkaloids, part 7     

Palladium(II)-dppe-arylazoimidazole complexes: Synthesis,and spectroscopic characterization

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.     

Synthesis,characterization and cytotoxic activity of diorganotin complexes with Schiff base derived from salicylaldehyde and l-tyrosine

Seven diorganotin complexes with the Schiff bases derived from salicylaldehyde and l-tyrosine, R₂Sn[2-O-5-XC₆H₃CH?=?NCH(CH₂C₆ H₄OH-4)COO] (X?=?H (1), Br (2); R?=?Me (a), Et (b), Bu (c), Cy (cyclohexyl) (d)), were synthesized and characterized by elemental analysis, IR, ¹H and ¹³C NMR spectra, and the single-crystal X-ray diffraction. In methanol, the racemization of chiral center of l-tyrosinate fragment occurred and the racemic products were obtained. X-ray analyses of 1c, 1d, and 2a–2c showed that the tin atoms of the complexes exhibit distorted trigonal-bipyramidal geometries. In 1c, 1d, and 2c, the intermolecular O–H???O hydrogen bonds connected the molecules into 1-D supramolecular chain or a R₂²(20) macrocyclic dimer, and 2a and 2b formed the 2-D supramolecular network by the intermolecular Sn???O and O–H???O interactions. Bioassay results indicated that 1a, 1c, and 1d had moderate antibacterial activity against Escherichia coli and 1c, 1d, and 2c belonged to the efficient cytostatic agents against two human tumor cell lines (A549 and HeLa) and the activity tends to follow the order Cy > Bu?>?Et?>?Me for the R group attached to tin.     

Homo- and hetero-dinuclear derivatives of aluminium containing Schiff-base ligands: synthesis,characterization and antibacterial activity of mononuclear derivative of aluminium

Reactions of Al(OPrⁱ)₃ with LH₂ =?[R′C(NYOH)CHC(R)OH] R=R′=CH₃, Y =?(CH₂)₂ (L¹H₂); R =?CH₃, R′ =?C₆H₅, Y =?(CH₂)₂ (L²H₂); R =?R′ =?CH₃, Y =?(CH₂)₃ (L³H₂); R =?CH₃, R′ =?C₆H₅, Y =?(CH₂)₃ (L⁴H₂), in 1 : 2 molar ratio give mononuclear derivatives of aluminium AlLLH (1a–1d). Equimolar reactions of AlLLH with M(OPrⁱ)₃ (M =?Al and B) yield homo- and hetero-dinuclear derivatives AlLLM(OPrⁱ)₂ (M=Al=2a–2d M=B=3a–3d). Reaction of 2a with L¹H₂ affords AlL¹L¹AlL¹ (4). All these derivatives have been characterized by elemental analysis, molecular weight measurements and plausible structures have been suggested on the basis of IR, NMR [¹H, ¹³C, ²⁷Al and ¹¹B] spectral data and FAB-mass studies of 2b and 3b. Schiff base L¹H₂ and its mononuclear derivative with aluminium (AlL¹L¹H) have been screened for their antibacterial activity against Escherischia coli and Bacillus subtilis.     

Syntheses and crystal structures of polymeric ionic triorganotin esters of 3,5-pyridinedicarboxylic acid and 5-nitroisophthalic acid

The triethylammonium dicarboxylatotriorganostannates, [(C₂H₅)₃NH][R₃Sn(3,5-pdc)]?·?mH₂O (3,5-pdc?=?3,5-pyridinedicarboxylate) (m?=?1, R?=?Me 1; m?=?0, R?=?Ph 2, PhCH₂ 3, n-Bu 4), [(C₂H₅)₃NH][R₃Sn(5-nip)] (5-nip?=?5-nitroisophthalate) (R?=?Me 5, Ph 6, PhCH₂ 7, n-Bu 8) have been prepared from triethylamine, 3,5-pyridinedicarboxylic acid, 5-nitroisophthalic acid and triorganotin chloride. Complexes 1–8 have been characterized by elemental, IR, ¹H, ¹³C and ¹¹⁹Sn NMR analyses. Complexes 1, 2, 5 and 6 are also determined by single crystal X-ray diffraction. For 1, 2, 5 and 6, each carboxylate moiety is involved in coordination to a tin center via only one O atom showing that the Sn atoms are five-coordinate and exist in trigonal bipyramidal geometries. Moreover, for 2, 5 and 6, the nitrogen atoms of ammonium are hydrogen bonded to the pendant carboxyl oxygen. In 1, adjacent polymeric chains and triethylammonium are linked by hydrogen bonds through the co-crystallized water molecule, thus a 2D network is formed.     

Reactions of trans-Carbonyl(Chloro)-[Bis(Triphenylphosphine)]Rhodium(I) with Substituted Cyclopentadienyl Tricarbonyl Molybdenum Anions

Reactions of trans-carbonyl(chloro)[bis(triphenylphosphine)]rhodium(I): trans-ClRh(CO)(PPh₃)₂ with substituted cyclopentadienyl tricarbonyl molybdenum anions, [Mo(CO)₃(η ⁵ -C₅H₄R)]^? (R=H; COCH₃) in tetrahydrofuran (THF) at 55°C for 24 h yielded two monometallic complexes as by-products: [Rh(CO)(PPh₃)(η⁵-C₅H₄R)] (R = H (1a); COCH₃ (2a)) and two main heterobimetallic compounds: [RhMo(CO)₄(PPh₃)₂(η⁵-C₅H₄R)] (R = H (1b); COCH₃ (2b)). These compounds were characterized by elemental analysis, IR and ¹H NMR spectra. The molecular structure of (2a) was determined by X-ray diffraction.     

New chemical constituents from the Piper betle Linn. (Piperaceae)

The phytochemical investigation of chloroform extract from Piper betle var. haldia, Piperaceae, leaves has resulted in the isolation of two new chemical constituents which were identified as 1-n-dodecanyloxy resorcinol (H1) and desmethylenesqualenyl deoxy-cepharadione-A (H4), on the basis of spectroscopic data 1D NMR (¹H and ¹³C) and 2D NMR (¹H-¹H COSY and HMBC) as well as ESI-MS, FT-IR and HR-ESI-MS analyses. Compounds H1 and H4 showed excellent antioxidant DPPH free radical scavenging activity with IC₅₀ values of 7.14 μg/mL and 8.08 μg/mL compared to ascorbic acid as a standard antioxidant drug with IC₅₀ value of 2.52 μg/mL, respectively. Evaluation of cytotoxic activity against human hepatoma cell line (PLC-PRF-5) showed moderate effect with the GI₅₀ values of 35.12 μg/mL for H1, 31.01 μg/mL for H4, compared to Doxorubicin^® as a standard cytotoxic drug with GI₅₀ value of 18.80 μg/mL.     

Syntheses and crystal structures of Dimolybdenum complexes containing P2 and functionalized Cyclopentadienyl ligands

The dimolybdenum complex [(η⁵-RC₅H₄)₂Mo₂(CO)₆] (1, R = CH₃CO; II, R = CH₃O₂C) reacts with an equimolar amount of white phosphorus P₄ to yield the corresponding dimolybdenum complex containing the P₂ ligand [(η⁵-RC₅H₄)₂Mo₂(CO)₄(μ,η²-P₂)] (1, R = CH₃CO; 2, R = CH₃O₂C) in moderate yield. The two new compounds have been characterized by elemental analyses, ¹H?NMR, ¹³C?NMR, ³¹ P?NMR and IR spectroscopies and their crystal structures have been determined by X-ray diffraction methods.     

含有席夫碱配体的钌配合物的合成、表征及抗肿瘤活性

设计并合成了3个含有席夫碱基团的配体（BLⁿ,n=1~3）及相应的双核联吡啶钌配合物[Ru （BLⁿ）（bpy）₂]₂（ClO₄）₄,其中bpy=2,2''-联吡啶,BLⁿ=（（PyCHN）-Ph-O-C₆H₄）₂R （PyCHN=N-2-吡啶亚甲基,R=none （Ru1）,—C （CH₃）₂（Ru2）,—SO₂（Ru3））。通过元素分析、核磁氢谱、红外光谱、质谱等方法对配体和配合物进行了表征。通过体外细胞毒性实验研究了Ru1~Ru3对宫颈癌细胞（Hela）、胃癌细胞（BGC823）、胃癌细胞（SGC-7901）三种肿瘤细胞和人正常胚肺成纤维细胞MRC-5的细胞毒性,实验结果表明Ru3的抗肿瘤活性最好,而Ru1~Ru3均对BGC823具有选择性。     

Synthesis and tautomeric transformations of 2-(tert-butyl)-1,2,4-benzotriazine-3(2H)-thiones

Treatment of 2-(tert-butyl)-1,2,3,4-benzotetrazinium tetrafluoroborates with sodium thiocyanate afforded 2-(tert-butylazo)phenyl isothiocyanates 3, which exist in equilibrium with 2-(tert-butyl)-1,2,4-benzotriazine-3(2H)-thiones 3′. The equilibrium depends on the substituents R in the benzene ring: the percentage of the open isomer 3 is about 20% for R = H or Me; for R = Cl or Br, the equilibrium is completely shifted to cyclic isomer 3′. The equilibrium is slow on the time scale of the ¹H and ¹³C NMR experiments. For compounds 3a/3′a (R = H), the spectra at 24 °C show two sets of signals, while those at 0 °C contain only signals for isomer 3′a. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1192–1195, July, 2006.     

Synthesis and Crystal Structures of Tetraazamacrocycle NickelII Complexes Containing O-Phenylenedioxydithiophosphate Anion

Abstract

A tetraazamacrocycle nickel^II complex of O,O′-diaryldithiophosphate, [Ni(hmtade)] [S₂P(O₂C₆H₄-o)]₂ (1), and its unexpected complex methanolysis product, [Ni(hmtade)] [S₂P(OMe)(OC₆H₄(OH-o)]₂ (2) (the ligand hmtade is 5,7,7,12,14,14-hexamethyl-1,4,8,11- tetraazacyclotetradeca-1,11-diene), have been synthesized and characterized by elemental analysis, IR, ¹H(¹³C, ³¹P) NMR spectroscopies, thermogravimetric analysis, and single-crystal X-ray diffraction methods. The results show that the difference in O,O′-diaryldithiophosphate anions hardly brings about any influence on the structure of complex cation [Ni(hmtade)]²⁺. In the packing of 1, the molecules self-assemble into a folded two-dimensional (2D) network and which further links into a complicated 3D supramolecular framework. Two different kinds of 2D networks form independently via intermolecular hydrogen bonds and alternatively arrange into a novel 3D lamellar sandwich-layer structure in the packing of 2.     

Hindered Rotation in Some Organic Dithiocarbamates

Abstract

Hindered rotation in alkyldithiocarbamates of the type RR′NC(= S)SR″ [R, R′, R″ = Me, Me, Et (1); PhCH₂, Me, Et (2); PhCH₂, H, Et (3); PhCH₂, H, Me (4) and O(CH₂CH₂)₂, Et (5)′ has been investigated using variable-temperature ¹H NMR spectroscopy in CDCl₃, C₆D₆, and DMSO-d₆ solutions. Rotational parameters were calculated by the coalescence temperature method. Nitrogen substituent effects on the free energy of activation and on the equilibrium constant of unsymmetrical conformers at room temperature are discussed.     

钌1,2-萘醌-1-肟配合物对aldol C—C成键反应的催化作用

在钌1,2-萘醌-1-肟(1-nqo)配合物cis,cis-[Ru(1-nqo)₂(CO)(NCMe)] (1)或trans,trans-[Ru(1-nqo)₂(PBu₃)₂] (2)的作用下, 氰基乙酸乙酯与取代苯甲醛发生aldol C—C成键反应. 根据GC-MS检测及HPLC分离结果, 对二苯甲醛的二个醛基可分别或同时与氰基乙酸乙酯发生aldol反应. ¹H NMR表征结果证明, 二种产物的双键构型均为反式. 其它取代苯甲醛的反应均给出单一反式aldol产物, 这表明该催化反应具有立体选择性. 配合物1的催化活性稍差, 产率不超过60%, 而配合物2的催化活性要高于1, 最高产率达99%.     

Diorganotin(IV) complexes with furan-2-carbohydrazone derivatives: synthesis,characterization, crystal structure and antibacterial activity

Four new diorganotin(IV) complexes, R₂SnL (L?=?L^a: R?=?Me 1, Ph 2; L?=?L^b: R?=?Me 3, and Ph 4), have been synthesized by reaction of hydrazone ONO donors, 5-bromo-2-hydroxybenzaldehyde furan-2-carbohydrazone (H₂L^a) and 2-hydroxynaphthaldehyde furan-2-carbohydrazone (H₂L^b) with diorganotin(IV) dichloride in the presence of a base. The compounds have been investigated by elemental analysis and IR, ¹H NMR, and ¹¹⁹Sn NMR spectroscopies. Spectroscopic studies show that the hydrazone is a tridentate dianionic ligand, coordinating via the imine nitrogen and phenolic and enolic oxygens. The structures of H₂L^b and 3 have also been confirmed by X-ray crystallography. The results show that the structure of 3 is a distorted square pyramid with imine nitrogen in apical position. The in vitro antibacterial activities of ligands and complexes have been evaluated against gram-positive (Bacillus cereus and Staphylococcus aureus) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. H₂L^a and H₂L^b show no activity but the diphenyltin(IV) complexes exhibit good activities towards two bacterial strains in comparison with standard bacterial drugs.