NCN-chelated organoantimony(III) and organobismuth(III) phosphates: synthesis and solid-state and solution structures

.Organoantimony(III) and organobismuth(III) phosphates (LM)(3)(PO(4))(2) [M = Sb (3) and Bi (4)], containing the NCN-chelating ligand L [L = 2,6-(CH(2)NMe(2))(2)C(6)H(3)], were prepared by the simple treatment of parent oxides 1 and 2 with H(3)PO(4). Both compounds were characterized by elemental analysis, electrospray ionization mass spectrometry, and IR and NMR spectroscopy and in the case of 3 by X-ray diffraction techniques. Compound 3 has an interesting behavior in solution, i.e., the formation of two possible conformational isomers, which was studied by (1)H, (13)C, and (31)P NMR spectroscopy.     

Synthesis and structures of organoantimony compounds containing intramolecular Sb-N interactions

Stibines containing the pendant arm [2-(Me₂NCHR)C₆H₄] (where R = H or Me) were synthesized, and their reactions with CH3I and HBr have been carried out to obtain the diammonium salt {[2-(Me₂NCHR)C₆H₄] [2-(Me₃N⁺CHR)C₆H₄]}Sb 2[I]⁻ (where R = H 3; Me 4) and triammonium salt {2-[(Me₂HN⁺CH₂)C₆H₄]₃}Sb 3[Br]⁻5, respectively. A novel platinum complex 6 [PtCl₂ · 1] containing stibine 1 as a bidentate ligand has also been prepared. All these compounds show Sb-N interactions. A good conjunction was observed between semi-empirical method and ¹H and ¹³C NMR (at different temperature) data for the diammonium salts of compounds 3 and 4. The structures of all the synthesized compounds were determined by X-ray diffraction analyses. This appears to be the second molecular structure of a Pt stibine complex containing a Pt-Cl bond trans to stibine ligand, as few Pt-Sb X-ray structures are known.     

Synthesis of enantiomerically pure Sb-chirogenic organoantimony compounds and their crystal structures

Sb-chirogenic organoantimony compounds (±)-5a-c bearing heteroatom moieties such as 4,4-dimethyl-2-oxazolinyl, methoxymethyl, and diphenylphosphanyl substituents on the o-position of an aryl group have been prepared by nucleophilic displacement of the ethynyl moiety on (1-naphthyl)(phenylethynyl)(p-tolyl)stibane (3) with aryllithium reagents (2a-c). The optical resolution of the racemic (±)-5a,b was attained via separation of a diastereomeric mixture of their palladium complexes (S)-7 formed from the reactions of (±)-5a,b with di-μ-chlorobis[(S)-dimethyl(1-ethyl-α-naphthyl)aminato-C²,N]dipalladium(II) (6). The enantiomerically pure Sb-chirogenic stibanes isolated here were optically stable, and no racemization on the chiral antimony center was observed even when they were allowed to stand at room temperature for over 72 h in chloroform. The structure of 5a,b including the absolute configuration was determined by single crystal X-ray analyses of (+)-5aB and antimony-palladium complex (7bB), respectively. The analyses also revealed the presence of intramolecular interaction between the antimony and sp²-nitrogen atoms in the molecule Sb(S)-(+)-5aB.     

Synthesis, crystal structures and in vitro antitumor activities of some organoantimony arylhydroxamates

A series of novel organoantimony arylhydroxamates with the formulae [Ar₃SbL₂]⁻[HNEt₃]⁺ (LH = arylhydroxamic acid; Ar = C₆H₅, 4-CH₃C₆H₄, 3-CH₃C₆H₄, 4-ClC₆H₄, 4-FC₆H₄) and (4-CH₃C₆H₄)₄SbL were synthesized and characterized by elemental analysis, IR, ¹H NMR and mass spectroscopy. The crystal structures of (4-CH₃C₆H₄)₄SbL and [Ph₃SbL₂]⁻[HNEt₃]⁺ were determined by X-ray diffraction. The in vitro antitumor activities of all compounds against three human cancer cells are reported.     

Syntheses and X-ray crystal structures of organoantimony diazides

Antimony(III) complexes of the general type LSbF(2) (3: L(1) =[tBuC(NiPr)(2)]; 4: L(2) =[tBuC(NDipp)(2) , Dipp=2,6-iPr(2)C(6)H(3)) and LSb(N(3))(2) (6: L(1); 7: L(2)) were prepared in high yields and characterized by elemental analyses, NMR and IR spectroscopy and single-crystal X-ray diffraction. Moreover, the solid-state structures of [L(2)SbF(2)][L(2)Li] (5), [L(2) AlH(2)] (1), and [L'H][L'K(thf)(3)] (2; L'=HC(NDipp)(2)) are described, in which the Li (5) and K atoms (2) adopt rather unusual coordination modes.     

Synthesis and structures of 6-methyl-1-(2-R-phenyl)-dihydropyrimidine-2,4-dione derivatives

N-Aryl--methyl--alanines were synthesized by the reaction of aromatic amines with crotonic acid. The products were converted to dihydropyrimidine-2,4-dione derivatives. Alkylation, acylotion, and oximation of 1-arylpyrimidine-2,4-diones were carried out. Conformational analysis of the compounds obtained was carried out by dynamic NMR methods.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1096–1106, August, 1990.     

Basicity of 4-aminopyrimidine and 2,4-diaminopyrimidine derivatives

Summary The basic dissociation constants for a series of 30 4-aminopyrimidine and 2,4-diaminopyrimidine derivatives were determined in 2% v/v aqueous methanol by a spectrophotometric method. The determinedpK _a values correlate well withHammet's constants.

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Basizität von 4-Aminopyrimidin- und 2,4-Diaminopyrimidinderivaten

Zusammenfassung Die basischen Dissoziationskonstanten einer Reihe von 30 4-Aminopyrimidin-and 2,4-Diaminopyrimidinderivaten wurden in 2% v/v wäßrigem Methanol durch spektroskopische Methoden bestimmt. Die ermitteltenpK _a-Werte korrelieren gut mit den entsprechendenHammett-Parametern .

     

Synthesis of 4-hydroxymethyl-2,4-methanoproline

The synthesis of 4-hydroxymethyl-2,4-methanoproline, a novel conformationally restricted amino acid, was performed in four steps. This close analogue of naturally occurring amino acids (i.e., proline, hydroxyproline, serine and threonine) was prepared in good overall yield through two intramolecular recyclization reactions of cyclobutane derivatives.     

1,3,5–三嗪–2,4–二酮衍生物的合成及其晶体结构研究

以尿素和4,5-二氮芴-9-酮为原料合成目标化合物,用1 H NMR、元素分析、FT-IR和X-射线单晶衍射进行了表征.晶体结构表明:化合物为单斜晶系,P21/n空间群,晶体学参数:a=0.710 89(9)nm,b=1.507 39(19)nm,c=1.344 95(16)nm,β=99.741(4)°,V=1.420 5(3)nm3,Z=4,Dc=1.591g·cm-3,Mr=339.16,μ=0.472,F(000)=696,R1=0.085 2,wR2=0.274 8[I2σ(I)].化合物通过氢键形成三维网状结构.     

Synthesis of 2,4-diphenyl-1H-pyrrol-1-amine derivatives

The direction of the reaction of 4-bromo-1,3-diphenyl-2-buten-1-one (γ-bromodypnone) with hydrazines depends on the nature of the substituent they contain. Reaction with 1-methylhydrazinium hydrosulfate gives 1-methyl-3,5-diphenylpyridazin-1-ium bromide but carboxylic acid hydrazides give N-(2,4-diphenyl-1H-pyrrol-1-yl)carboxylic acid amides. γ-Bromodypnone and phenylhydrazine give both 1,3,5-triphenyl-1,4-dihydropyridazine and N,2,4-triphenyl-1H-pyrrol-1-amine (15%). 1-(2,4-Dinitrophenyl)hydrazine gives the 2,4-dinitrophenylhydrazone of (Z)-4-bromo-1,3-diphenyl-2-buten-1-one. Condensation of 2,4-diphenyl-1H-pyrrol-1-amine with aromatic aldehydes readily leads to N-(arylmethylidene)-2,4-diphenyl-1H-pyrrol-1-amines and alkylation with methyl iodide gives N,N-dimethyl-2,4-diphenyl-1H-pyrrol-1-amine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–414, March, 2009.     

Synthesis of 2,4-dimethyl-6-oxo-2,4-heptadienoic acid derivatives from 2,4,6-trimethylpyrylium salts

Reaction 2,4,6-trimethylpyrylium salts with sodium cyanide in boiling water yielded the bicyclic lactone 1,3,5-trimethyl-6,8-dioxabicyclo[3.2.1]oct-2-en-7-one (6) along with a series of stereoisomers of 2,4-dimethyl-6-oxo-2,4-heptadienonitrile (5), which were the sole products when the reaction was carried out at room temperature. Compound 6, along with 3,5-dimethylphenol (7), was also obtained by refluxing 5 briefly in aqueous sodium hydroxide. However, when 5 was refluxed for a prolonged period in aqueous sodium acetate, 3,5-dimethyl-5-(2-oxopropyl)-furan-2-one (8), along with some 7, was generated instead. Compound 8 could also be produced from 6 on prolonged refluxing with aqueous sodium acetate, indicating that 6 was the kinetically-controlled and 8 the thermodynamically-controlled product.     

Synthesis and structures of some di- and triferrocenylmethane derivatives

Some triferrocenylmethane derivatives were prepared by reaction of triferrocenylmethanol (5) with triphenylcarbenium tetrafluoroborate followed by a nucleophile. Crystal structure analyses of triferrocenylmethane (7) and of 1,1,1-triferrocenyl-2,2-dimethylpropane (11) show that the conformation adopted by the triferrocenylmethyl group differs significantly with the steric bulk of the substituent at the central carbon atom. Treatment of 1,1′-bis(tributylstannyl)ferrocene (13) with 1 equiv. of butyllithium followed by chloroethylformiate affords complexes with one (14), two (15) or three ferrocenyl units (16) depending on the amount of chloroethylformiate used. Compound 16 is the first triferrocenylmethane derivative with substituents at the opposite cyclopentadienyl ring. Threefold lithiation of this compound is shown to work using butyllithium followed by dimethylformamide.     

Synthesis of 4-hydroxy- and 4-mercaptoquinazoline derivatives

The reaction of selenoesters with o-aminobenzamide and o-aminothiobenzamide derivatives led to the formation of 4-hydroxy- and 4-mercaptoquinazolines. Their structures were elucidated by means of elemental analyses and spectropic data (nmr and ms).     

Synthesis, characterizations and crystal structures of new organoantimony(V) complexes with various isomers of fluoromethylbenzoate ligands

Six new organoantimony(V) complexes containing various isomers of fluoromethylbenzoate ligands [RC₆H₃COO]₂SbPh₃ and [RC₆H₃COO]SbPh₄ [R = 3-F-4-(CH₃) (1, 4), 4-F-2-(CH₃) (2, 5), 5-F-2-(CH₃) (3, 6)] have been synthesized by the reactions of triphenylantimony(V) dichloride or tetraphenylantimony(V) bromide with various isomers of fluoromethylbenzoate ligands in 1:2 or 1:1 stoichiometries. All the complexes have been characterized by elemental analysis, IR and NMR [¹H, ¹³C and ¹⁹F] studies. The crystal structures of complexes 1, 3, 4, 5 and 6 have been determined by X-ray single crystal diffraction. The structure of complexes show that the five-coordinated antimony(V) atom adopts a distorted trigonal bipyramidal geometry. Furthermore, weak but significant intermolecular C–H···O, C–H···F hydrogen bonds, C–H···pi stacking lead to aggregation and assembly of these complexes into 1D and 2D supramolecular frameworks.     

Synthesis of some 2,4-disubstituted derivatives of the thiophene series from 4-chlordmethyl-2-acetothienone and 4-chlorome thyl-2-formylthiophene

Some difficult-to-obtain 2,4-disubstituted compounds of the thiophene series were synthesized starting from 4-chloromethyl-2-acetothienone and 4-chloromethyl-2-formylthiophene.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 490–492, April, 1973.The authors sincerely thank Professor Ya. L. Gol'dfarb for his constant interest in this research and for his valuable comments.     

Synthesis and study of 2,4-diamino-and 2-amino-4-(1H-pyrazol-1-yl)pyrimidine derivatives

New 2, 4-diamino-and 2-amino-4-(1H-pyrazol-1-yl) pyrimidine derivatives, which are of interest as mono-and bidentate ligands, were synthesized. From an examination of the UV, IR, and PMR spectra of the synthesized compounds it was concluded that they exist in the “amino” form. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–407, March, 1980.     

Synthesis of 4-thiouridine derivatives

The thionation of a protected uridine with the aid of P₂S₅ has given the corresponding 4-thiouridine derivatives, which have been phosphorylated at the 5 or the 2(3)hydroxyl. On being heated in aqueous pyridine solution with liquid hydrogen sulfide, cytidine phosphates also form 4-thiouridine phosphates. 4-Thiouridine 2,3-cyclophosphate has been obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 996–1000, July, 1973.The authors thank M. Ya. Karpeiskii for his constant interest in the work and for valuable critical observations.     

Synthesis, structure, and in vitro antiproliferative activity of cyclic hypervalent organobismuth(III) chlorides and their triphenylgermylpropionate derivatives

Six compounds of cyclic hypervalent organobismuth(III) chlorides and triphenylgermylpropionates bearing a nitrogen or sulfur atom as intramolecular coordination atom have been synthesized and characterized. The results of single-crystal X-ray analysis reveal that the eight-membered tetrahydroazabismocine rings are highly flexible. The Bi-S or Bi-N bond lengths in the thiabismocine or azabismocine derivatives are dependent on how the substituted groups are acting on the Bi, S or N atom. The replacement of the chlorine atom in azabismocine and thiabismocine with the triphenylgermylpropionic group (Ph₃GeCH₂CH₂COO) leads to the lengthening of Bi-N and Bi-S bond. The substituents connected with the nitrogen atom also have an effect on the Bi-N bond length of azabismocine. For example, a cyclohexyl group has electron-donating ability higher than a phenyl group; the replacement of the former by the latter would lead to the decline of Bi-N bond length and increase of C_Ar-Bi-C_Ar angle in the eight-membered ring. The in vitro antiproliferative activities of the fabricated materials were compared on gastric carcinoma cells by means of the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) method. It was found that the compounds show antiproliferative activity on gastric carcinoma cells (MGC-803) much higher than that of cisplatin. Moreover, there is enhancement of antiproliferative activity when the chlorine atom of the bismocine compounds is replaced by the triphenylgermylpropionic group, giving a low IC₅₀ value of 0.7 μM for thiabismocine triphenylgermylpropionate.