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We demonstrated, that based on carvone, new symmetrical AA-type monomers with double bonds can be easily prepared by thiol-ene or Michael addition of dithiols. Moreover, hydrosilylation reaction wi...

Using a “chiral pool” approach, a number of chiral thiolate and sulfide ligands based on natural terpenes and terpenoids have been synthesized in a few simple steps. Two new Rh-thiolate com...

Six antimony(III) heteroleptic derivatives of the type [(R)(R′)C = NO]2Sb[S2CNCH2(CH2)3C︹H2][where R= –C6H5, R′= –CH3 (A); R= –C6H4CH3, R′= –CH3 (B); R= –C6H4Cl, R′= –CH3 (C); R= –C6H4Br, R′= –CH3 (D); R= –C6H4OH, R′= –H (E); R(R′)C = C–CH2–(CH2)3–C︹H2 (F)] have been synthesized by the reactions of antimony trichloride with the sodium salt of substituted oximes and piperidine dithiocarbamate in 1:2:1 stoichiometry. These heteroleptic derivatives have been characterized by physico-chemical and elemental analyses (C, H, N, S and Sb). The tentative structures have been proposed on the basis of IR, 1H and 13C NMR spectral and LC-mass spectrometry. The oxime moiety behaves as a unidentate ligand whereas the dithiocarbamate moiety behaves in mono functional anisobidentate manner. Distorted trigonal bipyramidal geometry around antimony metal has been proposed for these derivatives. Powder XRD study revealed that derivative (A) has nano range particle size, which supports the crystalline nature of the derivative. These newly synthesized heteroleptic antimony(III) derivatives have been examined against the B. Subtilis (gram positive) and E. coli (gram negative) bacteria for antibacterial potential and two derivatives [(C6H5)(CH3)C = NO]2Sb[S2CNCH2(CH2)3CH2︹] (A) and [(C6H4CH3)(CH3)C = NO]2Sb[S2C NCH2(CH2)3CH2︹] (B) were examined for their antioxidant activity. Structural-activity relationship for antibacterial potential amongst the six derivatives (A-F) was also explored.

The synthesis of a new set of 2,3,4,5-substituted isoxazolidines having a sulfur containing heterocyclic moiety has been described. The structural features of the compounds have been analyzed by 1H and 13C NMR spectroscopy as well as by single crystal X-ray studies. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: .cif file.]

Zirconium(IV) Schiff base chelates having the general formula ZrL(OPr i )2 [where LH 2 = R CH 3 , R = –C 6 H 5 , –C 6 H 4 Cl(p)] were synthesized by the reaction of Zr(OPr i )4.Pr i OH with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry refluxing benzene. The complexes ZrL(OPr i ) 2 were used as important precursors for the synthesis of the complexes of the type Zr(L) 2 . The complexes, Zr(L) 2 , were prepared by the interaction of precursor ZrL(OPr i ) 2 with sterically constrained sulfur-containing Schiff bases of heterocyclic β -diketones in a 1:1 molar ratio in dry benzene. The structures of these zirconium(IV) chelates have been discerned with the help of elemental analyses, physicochemical studies, and spectral [IR and NMR ( 1 H and 13 C)] data. A distorted trigonal bipyramidal and a distorted octahedral geometry may be assigned to zirconium(IV) chelates of the types ZrL(OPr i ) 2 and Zr(L) 2 , respectively.

2-Silylated five-membered heterocycles can be easily accessed through reaction of bromo(methoxy)methylsilane and dithiols, mercapto amines, and mercapto alcohols. Further reaction of the obtained silylated heterocycles with electrophiles under fluoride ion conditions afford an easy functionalization of such molecules.

The optimization of the synthesis of 2,6-bis(trialkylsilyl)4H-thiopyranes and some aspects of the reactivity of the corresponding lithium salts with alkyl halides and benzaldehyde are presented.

The efficient synthesis of new sulfur-containing macrocycles via “click”-type alkyne–azide cycloaddition was described. Preliminarily, under aqueous conditions (water–methanol) using CuSO4/sodium ascorbate as a source of Cu(I), the yields of the products were very poor. Using the Cu(I) in nonaqueous solution (MeCN), the yields of the products grow significantly (approx. 50%).

Synthetic methods were developed to prepare ethyl (E)-4-[2-(3,4-dihydro-2-n-octyl-1-oxy-2H-1-benzothio-pyran-6-yl)-1-propenyl]benzoate ( 1 ) and ethyl (E)-4-[2-(3,4-dihydro-2-n-octyl-2H-1-benzothiopyran-6-yl)-1-propenyl]benzoate ( 10 ). These are the first examples of heteroarotinoids which possess properties of liquid crystals. The properties were evaluated using differential scanning calorimetry and by use of polarizing micrography. Both displayed textures which are typical of a smectic or cholesteric phase.

Studies on the chemical constituents of sulfur containing the 5-oxo-1,2,4-triazin-3-yl moiety are reviewed. The synthesis. unique features of the structures and biological significance of these constituents are discussed.

The sulfur containing bisphosphonic acids have been examined as a chondroprotective therapy for the treatment of arthritis. Several compounds have demonstrated both in vitro and in vivo activity. T...

The sulfur containing chemical agent, O-ethyl-S-2-(diisopropylaminoethyl) methylphospho-nothiolate (VX), is an extremely potent inhibitor of the enzyme acetylcholinesterase and exhibits extended neurological effects. It undergoes degradation on standing alone or in the environment. Hence, identification of its primary degradation products assumes considerable importance. The synthesis and mass spectral fragmentation behavior of the title compounds, some of which are present in the VX degradation products, has not received much attention. This communication describes the synthesis and mass spectral characterization of the title compounds.

Synthesis of novel benzothienopyridines, benzothienoquinoline, benzothienoxazines and benzothienopyrimidines utilizing 2-methyl-5,6,7,8-tetrahydro-4H-3,1-benzothienoxazine-4-one are reported. The structure of these compounds were confirmed by micro-analyses, IR, 1H-NMR and mass spectrometry. Preliminary biological studies of some compounds showed a promising radioprotection and antineoplastic activities.

Stereochemical studies of mono- and 2,3-disubstituted 1,4-dithianes and sulfur- and oxygen-containing macrocycles by means of NMR measurements, X-ray crystal structure analysis and molecular mechanics calculations revealed new conformational regularity and peculiarities.

[l-(4-N.N-dimethylaminosulfonephenyl)ethylidene]malononitrile 2a was used as starting material in the synthesis of thiophene. pyridine-2,6-dithione, pyrido[2,3-d]pyrimidine, 3,5-diarylaninline, enamine and enol ether derivatives.

Dialkyl phosphite adds to the C─N bond in 2H-1,3-thiazines 4 to give α-aminophosphonic acid esters 6. Starting from 2H-1,4-benzothiazines 5, the corresponding phosphonic acid esters 7 were obtained. For the first time C2-chiral 2H-1,3-thiazines 4a and 4b were used to investigate the diastereoselectivity of the addition reaction of dialkyl phosphite to those imine compounds.

Several new isolated or fused heterocyclic ring systems that accommodate the isothiouredo functionality, often associated with immunosuppressive activity, were synthesized for possible use as immunosuppressive agents. Preparation of these anchored heterocycles was achieved via a multi-step synthesis starting with the key intermediate thiazolyl thiourea derivative (I). Structure of the newly synthesized products was confirmed using both of elemental and spectral analyses.

Synthesis, characterization, and antimicrobial activities of some palladium(II) complexes of sulfur containing benzothiazolines having NS donor set are described. The resulting biologically active [Pd(NSH)2]Cl2 and [Pd(NS)2] type of complexes have been characterized by elemental analyses, molecular weight determinations and conductivity measurements. Based on infrared and 1H n.m.r. spectral studies a square planar structure has been established for all the derivatives. The benzothiazolines and their respective metal complexes have been screened for their antimicrobial activities.

The interaction between unsubstituted and p-substituted benzenesulfinic acids and various 2-halogeno-2-nitroethenylarenes at mol ratios sulfinic acid:2-halogeno-2-nitroethenylarene = 1:1 and 2:1 was studied at 0°C and 20°C for 16 and 96 hours. It was proved that, depending on experimental conditions, the reaction results not only in α-halogeno-α-nitro-β-sulfones but also in α-nitro-α,β-disulfones, which are obtained by a consecutive process. The quantitative ratio of these products and the isomer composition of some of them were determined by using high-performance liquid chromatography (HPLC).

A series of novel spiro [3H-indole-3, 2′-(1′H)[1, 2, 4]triazolo[5, 1-d][1, 3, 5]thiadiazepine]-2, 5′-(1H,4′H)-diones (II) have been synthesized by the condensation of novel 1, 3-dihydro-3-[(1H-[1, 2, 4]-triazol-3-yl)imino]-2H-indol-2-ones (I) with thioacids, viz. mercaptoacetic and 2-mercaptopropionic acid in dry toluene. I were prepared by the reaction of indole-2, 3-diones with 3-amino-1, 2, 4-triazole in absolute ethanol. All the compounds have been characterized on the basis of elemental and spectral studies and have been screened for their antibacterial activity.

A new general methodology for the construction of sulfur-containing heterocycles and crown thioethers based on facile, one-step ‘assembling’ of these molecules from αω-dithiols and alkynes via homolytic cycloaddition is developed.

The ketoxime-acetylene-based pyrrole synthesis provides two general versatile approaches to sulfur-containing pyrroles: (i) via sulfur-containing ketones, particularly such as acylated aryl sulfides or thiophenes and (ii) via thiylation reactions (including those via metallation) of N-vinylpyrroles or dithiocarbonization of pyrroles available from the reaction of ketoximes with acetylene or its synthetic equivalents. Syntheses of alkylthiopyrroles, alkylthioarylpyrroles, 2-(2-thienyl)pyrroles (and their N-vinyl derivatives), N-(alkylthio or arylthio)ethylpyrroles, pyrrole-1 - and pyrrole-2-dithiocarboxylates (by the reaction of pyrroles with carbon disulfide) and their derivatives such as functionalized 2-(1-alkylthiovinyl)pyrroles, 1-alkylthio-3-imino-3H-pyrrolizines, 1-alkylthio-3H-pyrrolizin-3-ones, are discussed.

A series compounds II–XII have been synthesized from the stereo-isomeric 4-{4-(Z)-[p-(benzenesul-fonyloxy)phenylmethylene]-5-oxo-1- phenyl-2-imidazolin-1-yl)-benzoic acid hydrazide derivative (I) in order to investigate the fungitoxic activity of the compounds against Rice blast pathogen “Pyricularia oryzae” and Brown leaf spot pathogen “Helminthosporium oryzae” and the possibility of their use as new sulfur-containing agro chemicals. Fungitoxicity of most of the synthesized products compared well with a standard commercial fungicide. The assigned structures for these potential fungitoxic agents were established by elemental analyses, spectral data and whenever possible by alternative synthetic routes.

Titanocenedicarbonyl, Cp2Ti(CO)2, activates the sulfur-sulfur bond in organic disulfides and sulfur homocycles like S6S7 and S8- Cyclic disulfides form chelating ligands with sulfur atoms attached to the Ti atom. The reaction with S6 yields a new compound with an eight sulfur atoms containing ligand. The novel titanocene compounds have been used as precursors for the synthesis of a series of methylene polysulfides.

The synthesis of some new sulfur containing spiroindole derivatives is reported. Spiro[2H-1,3-benzothiazine-2,3′-[3H]indole]-2′,4(1′H,3H)-diones and spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones were prepared by the reaction of 3-[2-(4-arylthiazolylimino)]-1,3-dihydro-2H-indol-2-one with o-mer-captobenzoic acid and mercaptoacetic acid respectively. Such spiro benzothiazineindoles are being reported for the first time. The compounds have been characterised on the basis of elemental and spectral studies.

The series of liquid crystals in which the rigid part is constituted by heteroaromatic cation (thiopyrylium, 1- 2 -dithiolium) have been synthesized. The nature of the mesophases depends on the number of flexible substituants grafted on the cationic units. Lamellar (SA) mesophases are obtained with two or three chains. With four paraffinic substituents columnar order (DH) appears.

The strained alkylidene episulfides were synthesized by carbene and alkylidene carbene additions to thiocarbonyl compounds. Thermal, photochemical, and acid catalyzed reactions have been extensively investigated, and and the transition metal-promoted reaction results in the first isolation of thioallyl iron tricarbonyl complex. Germylene and zirconocene also reacted with thioketene to give metallic analogue of alkylidene episulfides, which are excellent synthetic source of a variety of cyclogermanes and stable enethiolizable thioaldehyde. Thermal sulfurization of some 1,2,3-butatriene derivatives and 1,2,3-selenadiazoles with elemental sulfur has been examined to give a variety of novel cyclic polysulfides having an unique structure. Reactive silicon and germanium species also reacted with elemental sulfur and selenium to afford cyclic metallachalcogenides.

Heterophosphole3 derive from the classical nitrogen, oxygen or/and sulfur containing five-membered 6n-heterocycles by replacing a CH unit by two-coordinate phosphorus as a member of the ring. Formally 4 8 systems seem possible this way. Of 21 of them representatives have been prepared so far4.

The synthesis of some new sulfur-containing spiroindole derivatives is reported. Fluorinated 3′-aryl-2′-phenylimino-spiro[3H-indole-3,6′[4,5′-pyrazolin][4,3-d]thiazolo]2(1H)-ones were prepared by the reaction of 5-(2-oxo-3-indolinylidene)-3-aryl-2-phenylimino-4-thiazolidinones with hydrazine hydrate. The compounds have been characterized on the basis of elemental and spectral studies.

By reaction of arylazo-substituted aryl halides with mercaptides, new arylazo-substituted arylsulfides are formed. These compounds are deeply coloured and exhibit an intense absorption band in the visible region, which can be reproduced quantitatively and interpreted satisfactorily by means of quantum chemical calculations in the framework of the PPP and LHM methods, respectively.

The synthesis and coordination chemistry of ligands bearing PS donor groups in complexes with copper(I) halides, in particular thiophosphites, thiophosphonites, and thiophosphinites, are described.

In the reaction of 3,4,6,7-tetrachloro-2,5-dihydroxy-2,3-dihydro-benzo[b]furan with rubeanic acid 2,2'-bis[5-(3,4,6-trichloro-2,5-dihydroxyphenyl)thiazole] and 6-(3,4,6-trichloro-2,5-dihydroxyphenyl)-3-imino-3,4-dihydro-4H-1,4-thiazine-3-thione have been synthesized and after the oxidation the corresponding trichloro-1,4-benzoquinonyl-substituted sulfur containing heterocycles were obtained.

A variety of novel 1,3-butadienes with one or two sulfur-containing groups are easily accessible by sigmatropic rearrangement reactions. Furthermore, a new sequence of sigmatropic migrations leads to 1,2-difunctionalized 1,3-butadienes.

The possibility of the simultaneous treatment of petroleum refining and chloroorganic wastes (COW) has been shown. COW are complex mixtures of organic polychlorides. At present there are no effective and ecologically safe methods of COW remaking in the industrial practice. In fact, COW combustion or burial are used. Both are ecologically dangerous and can be used only as temporary measures.

Regioselective anodic monofluorination of 3-thiolanones, 1,3-oxathiolanones, and 1,3-dithiolanones was successfully carried out in MeCN containing Et3Ns3HF or Et4NFs4HF as a supporting electrolyte. Among the fluorinated products, 2-benzyl-4,4-dimethyl-2-ethoxycarbonyl-5-fluoro-3-thiolanone was found to possess comparable or even stronger in vitro human type II phospholipase A2 inhibitory activity compared with the known inhibitor, manoalide.

A series of new monocyclic diorganosilanes were prepared by condensation reactions of the appropriate diorganodichlorosilane with sulfur containing diols.1-3 The eight-membered rings containing bridging sulfinyl groups2 are positioned in anti chair-like conformations which precluded any additional coordination at silicon. This contrasts with silanes having sulfur1 or sulfonyl3 groups in place of sulfinyl in the ring system where Si–S or Si–O coordination was evident. In these molecules, X-ray studies showed1,3 that the rings has syn boat-like conformations.

Sulfur-containing cycloalkenes possessing disulfide units 1, 2, and 3 were obtained by oxidation of cis-disodium ethene-1,2-dithiolate, and their crystal structures were determined by the X-ray crystallographic analyses. Compound 1 was found to give the ring expansion product 3 in acetonitrile even at room temperature and also form reactive thioaldehyde under irradiation.

About 25% of the total production of amino acids world wide are sulfur containing amino acids. The applications, the technical syntheses and production methods are discussed with selected examples.

Besides the well-known zinc dithiophosphates (ZDTP) phosphorus and sulfur containing ashless additives are used to improve the lubrication properties of modern engine and hydraulic oils. It is generally accepted that a wear reducing reaction layer is formed by additive tribofragmen-tation reactions in the friction zone of the metal surface. The composition of those reaction layers and the formation mechanism relative to the used additive is quite unknown. By systematic modification of monothiophosphates the influence of molecule parameters on the wear reducing properties were investigated (1).