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A regioselective method for the synthesis of previously unknown bifuroxanyl systems containing the 3-nitrobifuroxanyl core, based on a cascade of one-pot reactions comprising of the acylation of dinitromethane sodium salt with furoxanyl hydroxamic acid chlorides, nitrosation of the acylation product with NaNO2/AcOH/AcONa, and intramolecular cyclization of the nitrosation product to give the 3-nitrobifuroxanyl moiety, has been developed.

Ring-fused tetrahydroquinolines with up to three contiguous stereogenic centers are obtained in high yields, excellent diastereoselectivities, and high enantioselectivities, starting either from imines or aldehydes.

A complete study on the preparation of original halogen-containing 4H-pyrido[e][1,3]oxazin-4-ones and their transformation into 1,2,4-oxadiazoles and 1,2,4-triazoles is presented. Starting from pyridyl-imide sodium salts, the efficiency of the intramolecular O-arylation was studied on three series of compounds, with different fluoro-, chloro-, and bromophenyl substituents at the C-2 position. The final halogenated compounds are of interest as new synthons for future functionalisation. We also present the discovery of a new, rapid, and complementary access to 2-substituted 4H-benzo[e][1,3]oxazinones. Finally, the one-step transformation of some of these pyrido-oxazinones into the corresponding hydroxypyridyl-substituted 1,2,4-oxadiazoles and 1,2,4-triazoles was explored, and the regioselectivity of the reaction was proved by X-ray crystallography.

Treatment of triazinones (I) with NaN3 provides sodium salts (II) instead of expected azides.

Efficient synthesis of trifluoromethyl and difluoromethyl-substituted oxindoles was achieved by reacting Langlois reagent or Baran reagent with N-arylacrylamides. However, the reaction of aryl sulfinic acid sodium salts with N-arylacrylamides did not give the desulfinative products, instead, aryl sulfonated products were produced.

Ethyl 6-amino-4-aryl-5-cyano-2,4-dihydropyrano[2,3- с ]pyrazole-3-carboxylates were synthesized via a four-component reaction of the sodium salt of diethyloxaloacetate, an aromatic aldehyde, hydrazine hydrate, and malononitrile. The products were obtained in moderate to high yields.

An iron-catalyzed sulfenylation and arylation of alkynes with aryl sulfinic acid sodium salts is described. Various aromatic sodium sulfinates acted both as aryl and sulfenylation reagents, affording tetrasubstituted alkenes in one pot with good yields.

The reaction of ortho-substituted arylsulfinic acid sodium salts with 3-phenylpropiolic acid gives β-keto sulfinones [cf.

A new, versatile method for the synthesis of, so far unknown, variously substituted 4-methylidenepyrazolidin-3-ones as potential cytotoxic agents is described. Target compounds were synthesized from the corresponding 4-diethoxyphosphorylpyrazolidin-3-ones which were used as Horner–Wadsworth–Emmons ­reagents for the olefination of formaldehyde. 4-Phosphorylpyrazolidin-3-ones were, in turn, obtained starting from the sodium salt of ethyl 2-diethoxyphosphoryl-3-hydroxy-2-propenoate, ethyl 2-acyl-2-diethoxyphosphorylacetates, or 3-methoxy-2-diethoxyphosphorylacrylate and monosubstituted or 1,2-disubstituted hydrazines.

The sodium salts of the conjugated bases of uracils undergo highly chemoselective O4-monoalkylation when treated with various alkyl halides in dry DMF, while the use of methyl iodide results in N1+N3-dimethylation. Theoretical evaluations of the chemo- and regioselectivity along with X-ray crystallographic data are presented.

The title compounds (III) (10 examples) are obtained by treatment of benzyl chloride (II) with the appropriate sodium salt of N,N-disubstituted dithiocarbamic acids (I).

A two-step sequence allows the synthesis of novel pyridooxazinones via aroylation of amides and subsequent intramolecular O-arylation of the resulting imide sodium salts.

A new and green method for the synthesis of α,β-unsaturated arylsulfones had been achieved through the condensation of aromatic aldehydes, chloroacetonitrile, benzenesulfinic acid sodium salt in the presence of 1-butyl-3-methyl imidazolium hydroxide ([bmim]OH) in EtOH under reflux. The ionic liquid was recovered and recycled for subsequent reactions. The advantages of this protocol were non-toxic, easy work-up and good yields.

A new protocol for the direct two-electron oxidative Umpolung of alkali halide salts is reported. This procedure, relying on the use of a commercially available sulfoxide as the oxidant, allows the electrophilic halogenation of carbonyl compounds as well as halolactonisation reactions to proceed from the corresponding sodium salts, at room temperature and under mild conditions.

23 Title compounds of type (IV), (VIII) and (XII) are prepared by a one-pot three-component reaction of enolizable ketones with nitriles and aromatic aldehydes.

Novel paramagnetic selective angiotensin AT1 receptor antagonists (sartans) bearing nitroxides (3, 4) have been prepared and their pharmacology evaluated in vitro as well as in vivo. Compounds 3, 4 proved to be effective sartans with pKB estimates in the range 6.2–9.1. In addition, the sodium salt (11) of 4 (R = Bu) is able to protect against vascular injury in hypertensive rats as determined by its ability to attenuate the development of intimal thickening caused by balloon injury of the carotid artery.

The sodium salt of α-formyl-γ-butyrolactone (I) is a versatile, reactive, and selective synthon giving access to several new heterocycles.

X-ray data of crystals of monensin A phenylurethane sodium salt (I) shows that the compound forms a pseudocyclic structure, stabilized by three intramolecular hydrogen bonds and the sodium cation coordinated by five oxygen atoms in the hydrophilic sphere.

A Pd-catalyzed desulfitative Heck-type reaction of aromatic sulfinic acid sodium salts with various olefins is developed with O2 as the terminal oxidant under mild conditions. The presence of phosphane ligand DPEphos in anisole can significantly enhance the reaction selectivity.

N-3-substituted dihydropyrimidinones are regioselectively prepared by using the title procedure concerning the reaction between dihydropyrimidinones, paraformaldehyde (II), chlorotrimethylsilane, alcohols, secondary amine, and sodium salts.

A series of acyclic and C-acyclic 7-deazapurine nucleosides have been synthesized and tested for antiviral activity. Reaction of the sodium salt of 2-amino-3,4-bis(aminocarbonyl)-5-(methylthio)pyrrole (6) with an appropriate electrophile gave pyrrole nucleosides which served as common intermediates to both the 7-deazaadenosine and the 7-deazaguanosine series. Several of these 5- and 5,6-substituted pyrrolo[2,3-d]pyrimidine nucleosides have shown activity against HIV virus in preliminary in vitro screens.

A series of sodium selenocarboxylates 2 were isolated from the reaction of diacyl selenides with sodium ethanolate and characterized. A convenient preparation of the sodium salts 2 by the direct reaction of acyl chlorides with sodium selenide was also established. The salts are colourless to slightly pale yellow crystals and labile towards moisture. They readily react with alkyl iodides at room temperature to give the corresponding Se-alkyl esters 3.

A synthetic scheme is described for the conversion of ethyl 2-hydroxyimino-3-oxobutyrate 3 into ethyl 2-(2-aminothiazol-4-yl)-2-vinyloxyiminoacetate 9via ethyl 2-{[2-(2-nitrophenylselenyl)ethoxy]imino}-3-oxobutyrate 5. The analogous 2-(1 -phenylvinyloxyimino)22 and 2-(isopropenyloxyimino)23 esters were obtained similarly from ethyl 2-hydroxyimino-3-oxobutyrate 3 or the corresponding methyl ester 25 by routes involving the epoxide-derived β-hydroxy selenides 2-(2-nitrophenylselenyl)1-phenylethanol 14 and 1-(2-nitrophenylselenyl)propan-2-ol 15. Subsequently ethyl 2-(2-aminothiazol-4-yl)-2-vinyl- 9 and 2-(1-phenylvinyl)-oxyiminoacetate 22 were successfully converted into the corresponding 6β-(substituted acetamido)penicillin sodium salts 11 and 24.

Some ethyl 5-aryl(or benzyl)-2-oxo-1,3,4-oxadiazole-3(2H)-acetates were prepared and treated with ammonia, primary amines or hydrazine to give 1-amino-2,4-imidazolidinedione or 1,3-diamino-2,4-imidazolidinedione derivatives. The 1,3-bis(benzylideneamino)-,2,4-imidazolidinedione was obtained by reacting ethyl bromoacetate with the 1,5-dibenzylidenecarbonohydrazide sodium salt

The synthesis of the-title compounds 9a, b, c′, f and of the sodium salts 10d, e, g starting with phthaloylglycyl chloride and the trimers 4a–d of methyleneamino-cyclopentane and -cyclohexane-carboxylic esters 3a–d is described. The products were devoid of any antibacterial activity.

Organotin(IV) derivatives of 3-phenyl and 3-p-chloro-phenyl-2-mercaptoquinazol-4-ones of the type , (R=Ph, n-Bu, Me; R′=C6H5, p-Cl-C6H4; n = 1,2) have been synthesized by the reaction of the sodium salt of the ligand with corresponding organotin(IV) chlorides in non-aqueous media. These compounds have been -characterized by elemental and spectral analyses. IR and NMR studies of these compounds show the monodentate behaviour of the ligand in the case of triorganotin(IV) derivatives and bidentate behaviour in the case of diorganotin(IV) derivatives.

Esterification of sodium salt of carboxilic acids were performed with alkyl bromide in phase-transfer conditions without solvent.

The Vilsmeier reaction of 3-nitropyrroles which are prepared by the reaction of nitroalkenes with the sodium salt of tosylmethylisocyanide gives 2-formyl-4-nitropyrroles in good yields.

tert- Alkyl sulfides are conveniently prepared from α-(1H-benzotriazol-1-yl)alkyl sulfides by displacement of the 1H-benzotriazol-1-yl group with Grignard reagents. The 1-[α-(alkylthio)alkyl]- and 1-[α-(arylthio)alkyl]-1H-benzotriazole intermediates are easily available by several routes: (i) displacement of the halogen from appropriate halides by sodium salts of thiols, (ii) condensation of 1H-benzotriazole and thiols with carbonyl compounds, or (iii) lithiation of N-substituted 1H-benzotriazoles and subsequent treatment with electrophiles.

Palladlum-catalyzed asymmetric allylic alkylatlon of 1,3-dlphenyl-2-propenyl acetate with sodium salt of dimethyl malonate and its derivatives has been successfully carried out in the presence of optically active diphosphine, such as (S)-BINAP. High enantioselectivity of up to 90% ee was obtained with dimethyl malonate.

Reactions of 2-phospholene 1-oxides with N-bromoacetamide in aqueous organic solvent produced 2-bromo-3-hydroxyphospholane 1-oxides, which reacted with sodium salts of dialkyl phosphonates to afford novel 2-phosphinoylphospholane 1-oxide derivatives. A 4-phosphin-oyl-2-phospholene derivative was also prepared.

Analogues of 3-nitro-1,2,4-triazol-5-one (NTO) have been synthesized. The strategy revolves around a new method for the synthesis of imidazolones, namely the addition-elimination reaction of the sodium salt of trimethylsilylethanol with a trimethylsilylethoxymethyl (SEM)-protected dinitroimidazole followed by the acid-catalyzed conversion to the desired nitroimidazole (5). The N-methyl derivatives of 5 were prepared in a similar manner starting from the N-methyldinitroimidazoles

Acid catalyzed etherification of 5-hydroxymethyluracil (3) afforded the corresponding 5-alkoxymethyluracils (4a-h). Treatment of the sodium salt of compounds (4a-g) with 4-bromobutyl acetate afforded 1,3-bis-(4-acetyloxybutyl)- (5a-g) and 1,4-acetyloxybutyluracil derivetives -6a-g). Alkylation of 4h with 5-chloropentyl benzoate gave 1,3-bis-(5-benzoyloxypentyl)- (8) and 1-(5-benzoyloxypentyl)-5-b-butyloxymethyluracil (9). Ammonolysis of 6a-g and 9 at room temperature gave the corresponding hydroxyalkyl derivatives (7a-g and 10)

Diphenylamine reacts with hexafluoroacetone to give a mixture of products, of which 2-(1-hydroxy-1-trifluoromethyl-2,2,2-trifluoroethyl)diphenylamine (II) was isolated. N-Arylanthranilic acids modify the 1,1,1,3,3,3-hexafluoro-2-hydroxy-2-propyl group upon the reaction of its sodium salt with the hydrate of hexafluoroacetone (I) under mild conditions. This method gave 4-(1-hydroxy-1-trifluoromethyl-2,2,3-trifluoroethyl)-N-(2,3-xylyl)anthranilic acid from N-(2,3-xylyl)anthranilic acid in 93% yield.

The reaction of the sodium salt of 2-amino-4-(4-pyridinyl)-1,3,5-triazine with t-butyl, isopropyl, phenyl, and p-chlorophenyl isocyanates formed the corresponding N-(alkyl or aryl)-2-amino-4-(4-piridinyl)-1,3,5-triazines whereas the reaction with methyl isocyanate and propyl isocyanate formed the expected N-alkyl-N'-[4-(4-pyridinyl)-1,3,5-triazin-2-yl]ureas

An efficient synthesis of a-phosphonothioamides is described, involving thioacylation of primary or secondary amines with a-phosphonodithioacid salts (prepared in situ), in the presence of boron trichloride. This method can also be used for the preparation of non-phosphorylated thioamides. In the same conditions and with thiophenol, a dithioacid sodium salt is converted into the S-aryldithioester, while an α-phosphorylated dithioacid sodium salt is reduced into the bis (phosphonomethyl) disulfide.

Individual sodium salts of branched perfluorocarboxylic acids, (CF 3 ) 2 CF(CF 2 CF 2 ) n COONa, and their analogs containing one chlorine atom, CF 3 CF(CF 2 Cl)(CF 2 CF 2 ) n COONa, were synthesized by telomerization of 2-iodoheptafluoropropane and 1-chloro-2-iodohexafluoropropane with tetrafluoroethene, the addition of ethylene to both types of iodides considered, HI elimination and the oxidation of perfluoroalkylethylenes with potassium bichromate

Reaction of glycidyl bromides and tosylates with the sodium salt of mercaptopyridine N-oxide led to the formation of episulphides.

Derivatives of two new molecular structures, namely, 7,8-dihydro-6H,10H-[1,2,5]thiadiazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazin-10-one and 6,7-dihydro-9H-thiazolo[3,2-a][1,2,5]thiadiazolo[3,4-d][pyrimidin-9-one, and derivatives of N-substituted sulfamic acid, namely, (8-amino-3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazin-6-on-7-yl)sulfamic acid and (7-amino-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidin-5-on-6-yl)sulfamic acid, were separated out as by-products in the reduction reaction of 8-amino-3,4-dihydro-7-nitroso-2H,6H-pyrimido[2,1- b][1,3]thiazin-6-one and 7-amino-2,3-dihydro-6-nitroso-5H-thiazolo[3,2-a]pyrimidin-5-one derivatives, respectively, with sodium hydrosulfite. A mechanism of reaction, which hypothesizes the action of sodium hydrosulfite in an asymmetic form, is proposed. The results of single-crystal X-ray investigation on 7,8-dihydro-6H,10H-[1,2,5]thiadiazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazin-10-one (R = 0.032 for 863 reflections) and (8-amino-3,4-dihydro-2H,6H-pyrimido[2,1-b]- [1,3]thiazin-6-on-7-yl)sulfamic acid, sodium salt (R = 0.028 for 3507 reflections) are reported.

Amidoximes 9a–d react with 1,3-dithia-2,4-diphosphetane-2,4-disulfides 1a–c at 110°C to give the corresponding 1,2,4-thiadiazaphosphol derivatives 10a–f. The sodium salt of benzamidoxime reacts with compound 1a to form the phosphonothiolothionate derivative 12, which reacts with alkyl iodide to yield S-alkyl derivatives 13a,b.

A new composite reagent, a combination of lead fluoride (PbF2) and a small amount of sodium salt (NaX, X = F, Br etc.) was found to be useful for facilitating heterogeneous fluorination of substituted benzyl halides in acetonitrile.

1,1'-Sulfonyldibenzotriazole (3) reacts with sodium alkoxides to give N-alkylbenzotriazoles. With alkanols, benzotriazolium alkyl sulfates are produced. 1-Benzenesulfonyl- 1,2,4-triazole with the sodium salts of alcohols gives 1 -alkyl-1,2,4-triazoles. The mechanisms of these reactions are discussed

The first synthetic route to racemic 6-(substituted methylene)oxapenems, an interesting new class of β-lactamase inhibitors, is described. In spite of their low hydrolytic stability, even the unprotected acids 9 and 10 can be isolated as their sodium salts. The 6-(unsubstituted methylene)oxapenem 7e, however, is unstable and decomposes under the conditions of its formation

The ab initio structures and energies of the isomers of NaAlCl n F 4-n (n=0-4) have been calculated at the HF/6-31G* level. Energies for their dissociation into ionic and neutral fragments are presentcd at the MP2/ 6-31G*//RHF/6-31G* and MP2/6-31+G*//RHF/6-31G* levels. Electron densities of AlCl 4 - , AlCl 2 F 2 - , AlF 4 - , and their sodium salts are reported and compared with electron densities for Na + Cl - and Na + F - . The agreement between the calculated and experimental equilibrium constants for the exchange reactions between the AlCl n F 4-n - (n=0-4) structures is remarkable