Synthesis,structure and cytotoxicity studies on diorganotin (R = Me,Et) complexes of N-methylpyridoxine (MePN,PN = Vitamin B6) containing different anions

The interaction of dimethyl- and diethyltin(IV) cations with methylpyridoxine iodide ([MePN]I; PN = pyridoxine) was studied in ethanol/water (80:20(v/v) containing Cl⁻, NO₃⁻ or I⁻ ions in different molar ratios. Several compounds containing the deprotonated (MePN-H) or neutral (MePN) ligand were isolated and characterized by elemental analysis, IR and NMR (¹H, ¹³C, ¹¹⁹Sn) spectroscopy and FAB mass spectrometry. The compounds [SnMe₂(MePN-H)](I₃), [SnEt₂(MePN-H)](I₃), [SnMe₂(MePN-H)(NO₃)], [SnEt₂(MePN-H)(NO₃)] and [SnMe₂(MePN)₂]I₂ were studied by X-ray diffractometry. The compounds in which the MePN-H ligand is present can be described as containing dinuclear [SnR₂(MePN-H)]₂²⁺ (R = Me, Et) units, in which two bridging chelating methylpyridoxinato ligands link two metal atoms. Interactions also exist between the metal and the I₃⁻ or NO₃⁻ anions and these interactions differ in degree and type. On the other hand, in the only example of a complex containing the MePN ligand, the mononuclear [SnMe₂(MePN)₂]²⁺ unit is present. The in vitro antitumor activity of these complexes against the HeLa, A2780 and A2780cis cell lines was determined and compared with that of the equivalent PN derivatives.     

Synthesis,spectral characterization,thermal, computational and antibacterial studies of lanthanide complexes with 2-fluorobenzoic acid-(5-R-2-hydroxy-benzylidene)hydrazide {R = chloro or bromo)

Tridentate Schiff base ligands, 2-Fluorobenzoic acid-(5-chloro-2-hydroxy benzylidene)hydrazide {H₂L_Cl} and 2-Fluorobenzoic acid-(5-bromo-2-hydroxybenzylidene)hydrazide {H₂L_Br} have been used to prepare a variety of lanthanide complexes [HNEt₃][LnL_x(NO₃)₂(H₂O)]H₂O, Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy and Er. The ¹H and ¹³C NMR of lanthanum in conjunction with the infrared, elemental, thermal, molecular mass and conductance measurements enable the assignment of the formula to these complexes. The anionic unit [LnL_x(NO₃)₂(H₂O)]^? contains one tridentate ONO-donor, L^2?, which coordinates the metal ions via the phenolate-O, the imine-N and the deprotonated amide-O atoms in enol tautomeric form. The coordination environment around central metal ion is completed by two bidentate nitrate ligands and one coordinated water molecule to give a coordination number of eight for Ln(III). In order to get a better insight into the structural features of the complexes, their molecular geometries were fully optimized using density functional theory calculations at the M06-2X/6-31G¹ level of theory. The antibacterial activity results, on a panel of six different bacterial strains, show that the activity of the complexes is higher than that of the free ligands and in some cases higher than that of amoxicillin which is taken as standard reference drug. Compared to the free ligands, the emission spectra of the complexes exhibit a blue-shift with a clear enhancement in the emission intensity.     

Synthèse et étude par spectroscopies infrarouge,Raman et Mössbauer de complexes de SnCln (n = 4, 5) avec Ph3PO,Ph3AsO et R4ZX (R = Me,Et ; Z = N,P et X = Cl,Br, SCN). Structure moléculaire de [C6H5COCH2NH3]2[SnCl6]

Synthesis, infrared, Raman and Mössbauer spectroscopic studies of SnCl_n (n = 4, 5) with Ph₃PO, Ph₃AsO and R₄ZX (R = Me, Et ; Z = N, P and X = Cl, Br, SCN). Molecular structure of [C₆H₅COCH₂NH₃]₂[SnCl₆]. SnCl₄-, SnCl₅⁻- and SnCl₆²⁻-containing compounds have been synthesized, and their Mössbauer and infrared spectroscopic studies undertaken. The environment around the tin centre is octahedral in all compounds. Infrared and Mössbauer spectroscopies show that the thiocyanate anion acts as a N-donor ligand. The X-ray structure determination of [C₆H₅COCH₂NH₃]₂[SnCl₆] has also been reported; this structure consists of octahedral SnCl₆²⁻ anions connected together into layers via hydrogen bonds between the chlorine and the hydrogen atoms of the NH₃⁺ groups of the C₆H₅COCH₂NH₃⁺ cations.     

The conversion of alkynes into substituted cyclopropanes effected by CH2I2-R3Al (R = Me, Et, i-Bu)

The reaction of mono- and disubstituted alkynes with CH₂I₂-R₃Al (R = Me, Et, i-Bu) was studied. It was found that the reaction of alkynes with CH₂I₂ in the presence of Me₃Al gives β-iodoethyl-substituted cyclopropanes. The use of Et₃Al or i-Bu₃Al affords exclusively cyclopropylic organoaluminum compounds.     

Synthesis,crystal structure and thermal behaviour of [La(hfa)3(Phen)2] (hfa = hexafluoroacetylacetonate,Phen = o-phenanthroline)

The mixed ligand complex [La(hfa)₃(Phen)₂] (I) was obtained by the interaction of La(hfa)₃ and Phen; its composition does not depend on the stoichiometry of the reagents. According to the X-ray single crystal analysis data, complex I crystallizes in the monoclinic space group P2₁/n, with a = 13.583(3) Å, b = 16.959(3) Å, c = 18.860(4) Å, β = 94.71(3)° and Z = 4. The structure of I consists of isolated mononuclear molecules, the coordination number of La being 10. Thermal behaviour and composition of the vapor phase have been studied for I by thermal analysis and mass-spectrometry using a Knudsen cell. The mixed ligand complex I was found to sublime congruently in the temperature range 370–460 K: [La(hfa)₃(Phen)₂]_(s) = [La(hfa)₃(Phen)]_(g) + Phen_(g), Δ_rH⁰(T) = 316.2 ± 1.8 kJ/mol.     

Synthesis,structure, and in vitro cytotoxicity of organoplatinum(II) complexes containing aryl olefins and quinolines

Ten new organoplatinum(II) complexes, [PtCl(Saf)(8-OQ)] (1), [Pt(Saf-1H)(8-OQ)] (2), [PtCl(Meug)(8-OQ)] (3), [Pt(Meug-1H)(8-OQ)] (4), [PtCl(Meteug)(8-OQ)] (5), [PtCl(Meteug)(Q)] (6), [Pt(Meteug)(Q-COO)] (7), [Pt(Eteug-1H)(Q)] (8), [Pt(Eteug-1H)(8-OQ)] (9), and [Pt(Eteug-1H)(Q-COO)] (10) (where Saf = safrole, Meug = methyleugenol, Meteug = methyl eugenoxyacetate, Eteug = ethyl eugenoxyacetate, Q = quinoline, 8-OQ = 8-hydroxyquinolinate, and Q-COO = quinolin-2-carboxylate), were synthesized and characterized by spectroscopic methods. The position of N and O donors of quinoline ligands in comparison with the ethylenic double bond and the aromatic C5 of the aryl olefins in platinum(II) coordination sphere of 1–10 was determined using their NOESY spectra and confirmed by single-crystal X-ray diffraction of 10. Complexes 1, 2, 3, 4, and 9 exhibit impressive activities on four human cancer cell lines KB, Hep-G2, Lu, and MCF7 with IC₅₀ = 1.4–9.6 μM. Complexes 1, 2, 4, and 9 gave better antitumor activity than cisplatin against examined cell lines.     

Spectroscopic properties of RBiBO4 (R = Ca,Sr) glasses doped with TiO2

Transparent glasses, melt quenching derived, containing 10RO·20Bi₂O₃·(70 ? x)B₂O₃·xTiO₂ [R = Ca, Sr] with x = 0, 0.5, 1.0 wt% were characterized by X-ray powder diffraction. Physical and spectroscopic properties viz., density, absorption, emission, electron paramagnetic resonance (EPR) and FTIR were investigated. The absorption band around 823 nm in pure glass samples is attributed to the electronic transition of ³P₀ to ³P₂ of Bi⁺ radicals. A small absorption hump centered around 609 nm is found in all doped glasses due to ²T_2g to ²E_g transition of octahedral Ti³⁺ ions. The emission results revealed that all the samples exhibit a broad emission band covering entire visible-light range, with λ_ex = 360 nm, centered 470–520 nm corresponds to electronic transition of ³P₁ to ¹S₀ of Bi³⁺ ions, therefore the present materials can be potentially used as tunable or full-color display systems. And a strong emission around 706 nm with λ_ex = 514 nm due to transition of ²P_3/2 to ²P_1/2 of Bi²⁺ ions. In SrO mixed glasses Ti⁴⁺ ions effect the environment of Bi³⁺ ion symmetry units from C₂ to C_3i. A small EPR signal (at room temperature) is observed in titanium doped glasses due to Ti³⁺ ions. In both the series with increase of TiO₂ concentration BO₄ units are gradually converted into BO₃ units and new cross linkages are formed, like B–O–Ti, Bi–O–Ti at the expense of B–O–B bonds.     

Synthetic and structural studies of NHC–Pt(dvtms) complexes and their application as alkene hydrosilylation catalysts (NHC = N-heterocyclic carbene,dvtms = divinyltetramethylsiloxane)

The synthesis and structural characterization of a series of platinum complexes, bearing N-heterocyclic carbenes (NHC) and divinyltetramethylsiloxane (dvtms) as supporting ligands, are described. The reaction of commercially available Karstedt’s catalyst (Pt₂{(η²-ViSiMe₂)₂O}₃) with in situ generated NHC leads to monomeric platinum(0) complexes in which one NHC is bound to the metal center, as indicated by spectroscopic analysis and single-crystal X-ray diffraction studies. The relative reactivity trend for these complexes as catalysts for the hydrosilylation of alkenes is discussed in terms of NHC ligand steric properties.     

Synthesis,characterization and binding studies of novel diorganotin(IV) complexes of sodium 2‐mercaptoethanesulfonate

Diorganotin(IV) complexes ( 1‐4) of MESNA (sodium 2‐mercaptoethanesulfonate HSCH₂CH₂SO₃Na) and a mixed ligand complex of dibutyltin(IV), 1,10‐phenanthroline and MESNA ( 5 ) were synthesized with thermal and microwave assisted methods. All the complexes were characterized thoroughly with the help of analytical and various spectroscopic techniques viz. FTIR, NMR (¹H, ¹³C, and ¹¹⁹Sn NMR) spectroscopy and ESI‐MS spectrometery. Various spectrophotometric studies were carried out to decipher the binding mode of MESNA and its diorganotin complexes 1 ‐ 5 with calf thymus DNA (CT DNA) and thus, to calculate the binding constant (K_b). Absorption spectrophotometric study confirmed the interaction is through partial intercalation of all the complexes including MESNA, inside the DNA helix and calculated binding constant (K_b) is in the order of 10³ M^‐1. A series of emission spectrophotometric experiments support the results obtained through the absorption spectrophotometric studies. Circular dichroic (CD) spectroscopic analysis and viscosity measurement of CT DNA further complemented the fact that the partial intercalation plays a major role in the interaction of the studied complexes with CT DNA. All the studies corroborated that complex 2 bound to CT DNA with maximum affinity followed by complex 5 among all the complexes. Involvement of hydroxyl radicals as an active species in the cleavage activity of pBR322 plasmid DNA is proved by carrying out agarose gel electrophoretic technique.     

Carbonyl rhodium(I) complexes containing (H)PNX (X = O or N) ligands deriving from natural aminoacid–amides. Synthesis, X-ray structure and spectroscopic characterization

The polyfunctional (H)PNX (X = O or N) ligands 1 and 2 react with [Rh(CO)₂Cl]₂ to give the corresponding chloro carbonyl complexes {Rh[κ²-(H)PN](CO)Cl} (1a and 2a), where the neutral ligands coordinate in a κ²-PN bidentate fashion, the square planar coordination being completed by the CO trans to N and the chloride trans to P. In chloroform solution 1a maintains its original structure, while 2a partially transforms into the cationic species {Rh[κ³-(H)PNO](CO)}Cl. The chloroform solutions of 1a and 2a react with AgPF₆ to give the purely cationic species {Rh[κ³-(H)PNO](CO)}PF₆ ([1a]⁺ and [2a]⁺), while addition of Et₃N originates the neutral species {Rh[κ³-PNN′](CO)} (1b and 2b). All the complexes have been characterized by microanalysis, IR, ¹H NMR as well as ³¹P{¹H} NMR spectroscopy. The X-ray structures of ligand 1 and complex 1b are also reported.     

First cyclotrisiloxanes with three different R2Si-units of the general formula R2Si(OSiR2)(OSiR2)O (R2 = Me2Si(NSiMe3)2, R = Cl, Ot-Bu, R = Me)

The reaction of compound Me₂Si(NSiMe₃)₂Si(OH)Cl with Me₂SiCl₂ leads to the disiloxane Me₂Si(NSiMe₃)₂Si(Cl)OSi(Me₂)Cl (1). Hydrolysis of 1 in the presence of pyridine results in Me₂Si(NSiMe₃)₂Si(OH)OSi(Me₂)OH (2), which is allowed to react with SiCl₄ to give cyclotrisiloxane [Me₂Si(NSiMe₃)₂Si](OSiMe₂)(OSiCl₂)O (3). The treatment of 1 with (t-BuO)₂Si(OH)₂ forms cyclotrisiloxane [Me₂Si(NSiMe₃)₂Si](OSiMe₂)[OSi(Ot-Bu)₂]O (4). Compound 3 is obtained as a crystalline solid while 4 is an oily liquid. The ring size of these new types of cyclotrisiloxanes with three different R₂Si-units is confirmed by cryoscopy in benzene, ²⁹Si NMR chemical shifts and in case of 3, additionally by a single X-ray diffraction study. The different electronegativities of the substituents in the R₂Si-units lead to different bond lengths and bond angles within the Si₃O₃ cycle, which are discussed in detail in the molecular structure of 3.     

Synthesis,spectral analysis and in vitro cytotoxicity of diorganotin (IV) complexes derived from indole-3-butyric hydrazide

A series ( 1–20 ) of diorganotin (IV) complexes with general formula R₂SnL were formed by the reaction of R₂SnCl₂ (where R = Me, Et, Bu and Ph) with Schiff base ligands ( H ₂ L ^1–4 ) derived from the reaction of indole-3-butyric hydrazide with the salicylaldehyde and its derivatives. The structure elucidation of compounds were done by using UV–Vis, FT-IR, NMR (¹H, ¹³C, ¹¹⁹Sn), Mass spectrometry and thermal gravimetric analysis. Spectroscopic evidences suggested tridentate nature (ONO) of Schiff base ligands and coordinated to the dialkyl/diaryltin (IV) moieties through nitrogen and oxygen donor sites giving pentacoordinated geometry to complexes. The compounds were tested for the antimicrobial activity against bacterial and fungal strains which showed promising biological activity with compound 20 (Ph₂SnL⁴) as most active against microbes. The in silico study of the compounds was carried and observed that the compounds are used as orally active drugs and promote the formation of different hydrazide based drugs. The synthesized compounds were tested against human carcinoma cell lines namely A549, MCF7 and one normal cell line IMR 90 using MTT assay. The diethyl and dibutyltin complexes of Schiff bases displayed good cytotoxic activities. Compound 3 (H₂L³) and 10 (Et₂SnL²) were most potent against cancer cell lines with lowest IC₅₀ values and 7–8 times less toxic against the normal cell line.     

Synthesis, structure, and reactions of binuclear gold(I) complexes containing two different bridging ligands

The binuclear cycloaurated compounds [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(2)] (n = 5, 1a; n = 6, 1b) react with the digold(I) complexes [Au(2)(mu-S(2)CN(n)()Bu(2))(2)] and [Au(2)(mu-dppm)(2)](PF(6))(2) to give heterobridged dinuclear complexes [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(mu-S(2)CN(n)Bu(2))] (n = 5, 5a; n = 6, 5b) and [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(mu-dppm)]PF(6), (n = 5, 9a; n = 6, 9b), respectively. Complex 5a exists in the solid state as an infinite zigzag chain of dimeric units with intramolecular Au-Au separations of 2.8331(3) and 2.8243(3) A for independent molecules and intermolecular Au-Au separations of 3.0653(3) and 3.1304(3) A. Both 5a and 5b undergo oxidative addition with halogens to give the heterovalent, gold(I)-gold(III) compounds [XAu(I)(mu-2-Ph(2)PC(6)H(3)-n-Me)Au(III)X(eta(2)-S(2)CN(n)Bu(2))] [n = 5, X = Cl (6a), I (8a); n = 6, X = Cl (6b), Br (7b), I (8b)]. Compound 8a has been shown by X-ray crystallography to contain a gold(III) atom coordinated in a planar array by bidentate, chelating di-n-butyldithiocarbamate, iodide, and the sigma-aryl carbon atom, together with a gold(I) atom that is linearly coordinated by the phosphorus atom of the arylphosphine and by iodide. The intramolecular gold-gold distance of 3.2201(3) A indicates little or no interaction between the metal atoms. In contrast to the behavior of the homobridged complexes 1a and 1b, the heterobridged dithiocarbamate complexes 5a and 5b give structurally similar products on reaction with halogens, irrespective of the position of the ring methyl substituent. Crystal data for [Au(2)(mu-C(6)H(3)-2-PPh(2)-5-Me)(mu-S(2)CN(n)Bu(2))] (5a): triclinic, space group P1 (No. 2), with a = 11.3398(1), b = 15.9750(2), c = 16.4400(3) A, alpha = 91.0735(9), beta = 109.3130(7), gamma = 90.7666(8) degrees, V = 2809.47(6) A(3), and Z = 4. Crystal data for [IAu(I)(mu-2-Ph(2)PC(6)H(3)-5-Me)Au(III)I(eta(2)- S(2)CN(n)Bu(2))] (8a): triclinic, space group P1 (No. 2), with a = 8.6136(2), b = 9.3273, c = 21.1518(4) A, alpha = 84.008(1), beta = 84.945(1), gamma = 75.181(1) degrees, V = 1630.54(6) A(3), and Z = 2.     

Synthesis,crystal structures,and cytotoxicity of 2-benzoylpyridine N(4)-cyclohexylthiosemicarbazone and its zinc(II) and diorganotin(IV) complexes

[Zn(L)₂] (1) and [(Ph)₂Sn(L)(CH₃COO)] (2), where HL = 2-benzoylpyridine N(4)-cyclohexylthiosemicarbazone, have been synthesized and characterized. The complexes show different coordination depending on their coordinating preferences. Biological studies carried out in vitro against human leukemia K562 cells show that the diorgantin(IV) complex, 2, has significant cytotoxicity with IC₅₀ = 3.3 ± 0.5 μM.     

Synthesis,structure, and photophysical property of series of Ln(III) coordination polymers with different carboxylato ligands (Ln = Sm,Eu)

Four Ln(III) coordination polymers, {[Ln₂(1,3-bdc)₃(H₂O)₄]·DMF·H₂O} _n (Ln = Sm 1, Eu 2) and [Ln₂(mal)₃(H₂O)₆] _n (Ln = Sm 3, Eu 4) (1,3-H₂bdc = isophthalate acid, H₂mal = malonate acid), were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, UV–Vis–NIR absorption spectra, and fluorescence spectra. The structural analyses reveal that polymer 1 is a 3D coordination polymer. Its asymmetry unit contains two crystallographically independent Sm(III) ions, both are eight-coordinated. The 1,3-bdc^2? anions show three different coordination modes. The structure of polymer 2 is isomorphous with that of 1. Polymer 3 is also a 3D coordination polymer, its asymmetry unit contains one Sm(III) ion, which is nine-coordinate. The mal^2? anions have two different coordination modes. The structure of polymer 4 is isomorphous with that of 3. The luminescent study shows that polymers 1, 2, and 4 exhibit characteristic emission bands in the visible region, corresponding to the transitions of the Ln(III) ions. By comparison and analysis of luminescence, it is found that the incidence of the same ligand on the corresponding spectra of different Ln(III) ions is different, and the influence of different ligands on luminescence of the same Ln(III) ion is also very different.

     

Synthesis, characterization and structural studies of diorganotin(IV) complexes with Schiff base ligand salicylaldehyde isonicotinylhydrazone

Eight diorganotin(IV) complexes of salicylaldehyde isonicotinylhydrazone (H₂SalN) R₂Sn(SalN) R = t-Bu 1, Ph 2, PhCH₂3, o-ClC₆H₄CH₂4, p-ClC₆H₄CH₂5,m-ClC₆H₄CH₂6,o-FPhCH₂7, p-FC₆H₄CH₂8 were prepared. All complexes 1-8 have been characterized by elemental, IR, ¹H, ¹³C and ¹¹⁹Sn NMR analyses. The crystal structures of H₂SalN and complex 1 were determined by X-ray crystallography diffraction analyses. Studies show that H₂SalN is a tridentate planar ligand. For complex 1, the tin atom lies in this plane and forms a five- and six-membered chelate ring with the tridentate ligand. A comparison of the IR spectra of the ligand with those of the corresponding complexes, reveals that the disappearance of the bands assigned to carbonyl unambiguously confirms that the ligand coordinate with the tin in the enol form.     

The synthesis and deep purification of GaEt3. Reversible complexation of adducts MAlk3 (M = Al, Ga, In; Alk = Me, Et) with phenylphosphines

Optimal parameters of organomagnesium technique of synthesis of triethylgallium have been defined. Various techniques of deep purification of triethylgallium to the extent required in metalorganic vapor-phase epitaxy MOVPE have been studied: by way of residue ether displacement through high-performance rectification and interaction with high pure aluminum and gallium trichloride, and by way of reversible complexation with triphenylphosphine, 1,3-bis(diphenylphosphine)propane and 1,5-bis(diphenylphosphine)pentane. Advantages and disadvantages of each technique have been identified. We have shown high performance of adduct purification technique covering trimethyl and triethyl derivatives of aluminum, gallium and indium. The structure of donor-acceptor complexes between metal alkyls and the above-mentioned phosphines have been verified using H and ³¹P NMR spectroscopy and X-ray studies, as well as quantum chemical calculations. Thermal stability of triethylgallium and oxidation of its adducts with phosphines have been studied.     

Synthesis and spectral studies of diorganotin(IV) dialkyldithiophosphates

Two series of diorganotin(IV) dialkyldithiophosphates, [RR′Sn{SSP(OR″)₂}₂](R = Me or Et; R′= Ph; R″ = Et, Prⁿ, Prⁱ or Buⁿ) and [RR′Sn(Cl){SSP(OR″)₂}] (R = R′= Me, Et or Ph; R″ = Ph; R″ = Et, Prⁱ or Buⁿ) were prepared and characterised by i.r. and NMR (¹H, ¹³C, ³¹P, ¹⁹⁹Sn) spectroscopy. The NMR data indicate five and six coordinate geometries for [RR′Sn(Cl){SSP(OR″)₂}] and [RR′Sn{SSP(OR″)₂}₂] complexes, respectively. The chloro complexes showed ²J (PSn) whereas such couplings were not observed in the spectra of [RR′Sn{SSP(OR″)₂}₂].     

Synthesis,characterization and in vitro antitumour activity of diorganotin bisxanthates [R2Sn(S2COR′)2] (R=Me,Et, nBu,Ph; R′=Et,iPr, Hex) and crystal structure of bis(O-ethyldithiocarbonato)diphenyltin(IV)

A series of diorganotin bisxanthate compounds, [R₂Sn(S₂COR′)₂] (R=Me, Et, nBu, tBu, and Ph; R′?Et, iPr and cHex) have been prepared and characterized by spectroscopic methods (IR, NMR and FAB MS). The xanthate ligands chelate the R₂Sn moieties forming disparate Sn–S bonds leading to skew-trapezoidal biypramidal tin atom geometries. The crystal structure of a representative compound, [Ph₂Sn(S₂COEt)₂], confirms the spectroscopic results and shows the tin atom to be coordinated by two asymmetrically chelating xanthate ligands [Sn–S(1) 2.486(1), Sn–S(2) 3.052(1) Å and Sn–S(3) 2.484(1), Sn–S(4) 3.220(1) Å] with the two phenyl substituents lying over the weaker Sn–S interactions so that C–Sn–C is 126.5(1)°. Crystal data for [Ph₂Sn(S₂COEt)₂]: monoclinic space group P2₁/n: a=9.645(1), b=23.723(3), c=9.798(2) Å, ß=100.23(1)°, V=2206.2 ų, Z=4; 2708 data refined to final R 0.023. A selection of these compounds has been evaluated for activity against the L1210 mouse leukaemia cell line.