Studies on isoindoline derivatives and related compounds. I Synthesis and reduction of 1,3-dicarboethoxymethyleneisoindoline

The reaction of iminoether III with benzyl cyanoacetate gave ethyl 1-(α-cyanocarbobenzyl-oxymethylene)isoindoline-3-acetate (V) in a 26% yield. Decarboxylation of ethyl 1-(α-cyanocarboxymethylene)isoindoline-3-acetate (VI), obtained by hydrogenolysis of V, gave a mixture of 1-carboethoxymethyleneisoindoline-3-acetonitrile (VII) as major component and 1-carboethoxymethylene-3-cyanomethyleneisoindoline (VIII) as minor component, which were reconvertible into each other. On the other hand, decarboxylation of VI was successfully carried out to give VII as a single product under a nitrogen atmosphere. Ethanolysis and autoxidation of VII gave crystalline diethyl 1,3-dicarboethoxymethyleneisoindoline (XIII). Catalytic hydrogenation of of XIII over platinum oxide gave diethyl isoindoline-cis-1,3-diacetate (XIV) in a yield of 92%. The uv spectra of these 1,3-disubstituted isoindoline derivatives are summarized in Table I.     

Meldrum's acid and related compounds in the synthesis of natural products and analogs

This critical review focuses on applications of Meldrum's acid and its derivatives to the synthesis of natural products and analogs. It covers all relevant literature from 1991 to August 2007 (181 references).     

Studies on pyridazine compounds,XIX. Mesylation of 5-aminopyrazoles and related compounds

Summary Acylation of 5-amino-1-substituted pyrazoles gave — depending on the substituents in position 3 and agents used — mono-, di- and triacylated products, respectively.Poster presented at the 10^th International Congress on Heterocyclic Chemistry, Waterloo/Canada, August 11–16, 1985.     

Polysiloxane zwitterionomers and related model compounds. I. Synthesis

Polymers containing zwitterions were prepared by reacting γ-propanesultone with polydimethylsiloxane-co-(4,7-diazaheptylmethylsiloxane), which generated substituted di(ammonium-3-propane-sulfonate) groups pendant from the siloxane chain. Their concentration in the polymers varied from 0.5 to 10 mole %. Two model compounds were also prepared in order to (1) characterize the reaction leading to the formation of these zwitterions and (2) characterize the ionic forces in solutions (tetrahydrofuran and benzene were used as solvents). The degree of aggregation of these model compounds was higher in tetrahydrofuran and increased in both solutions with the concentration. No rearrangements of siloxane bonds were observed in the presence of these zwitterions or γ-propanesultone.     

Diisophorone and related compounds—I: Dimerisation products of 3-methylcyclohex-2-enones

Depending on the conditions, the self-condensation of 3-methylcyclohex-2-enones produces one or more of several possible dimeric products, including tricyclo[7,3.1,0^2.7] tridecane derivatives. Some general structural and spectral features of this class of compounds are discussed, and a simplified method of naming its members is proposed.     

Studies of pyrans and related compounds

The fine structures of the products of the cleavage of the heterorings of chromones and 4-pyrones by ammonia and primary and secondary amines, i.e., 2--aminoacrylylphenols (I) and di(-aminovinyl) ketones (II), were studied by means of IR and PMR spectra, and it was established that I and II, which contain amino groups with a hydrogen atom attached to the nitrogen, exist in the cis form with double intramolecular (chelate) bonding between one carbonyl and two proton-containing groups.See [27] for communication XLIII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 723–729, June, 1971.     

Studies on imidazole derivatives and related compounds. I. Synthesis of novel antineoplastic derivatives of 4-carbamoylimidazolium-5-olate

Acylation of 4-carbamoylimidazolium-5-olate ( 2 ) with a variety of acid chlorides produced 4(5)-carbamoyl-1H-imidazol-5-(4)yl acid carboxylates ( 3a-j ). Treatment of esters 3a,c with sodium hydroxide gave imides, 4a,c . Methylation of 3a and 2 with diazomethane gave the N-3 methyl derivative ( 6 ) and a mixture of the N-3, O-dimethyl derivative ( 9 ), the N-1, N-3-dimethyl derivative ( 10 ) and the O-methyl derivative ( 11 ), respectively. 5-Carbamoyl-1-methylimidazolium-4-olate ( 7 ) and its 4-carbamoyl isomer ( 16 ) were prepared from 2-aminopropanediamides 8 and 15 , respectively. Treatment of the imidazolium compound ( 10 ) with aqueous potassium hydroxide gave the recyclized product, 1-methyl-5-methylcarbamoylimidazolium 4-olate ( 18 ). Methyl derivatives 6, 7 , and 9 except 16 demonstrated the complete lack of antitumor activity against Lewis lung carcinoma or sarcoma 180 in mice.     

Studies on isocyanides and related compounds. An unusual synthesis of imidazolyloxazolones

The reaction between ethyl (Z)-3-dimethylamino-2-isocyanoacrylate ( 1 ) and arenesulfenyl chlorides 6a-c afforded the unexpected imidazolyloxazolones 7a-c . The structure of compounds 7a-c was in agreement with their ¹H nmr, ir and ms data and was confirmed by X-ray analysis of 7a .     

Studies on complex compounds of thorium(IV) with pyridine and quinoline carboxylic acid. Part I

Summary Thorium acetylacetonate [Th(acac)₄] reacts with pyridine carboxylic acids in acetone giving eight coordinate thorum(IV) complexes of the compositions [Th(pic)₄] and [Th(picO)₄] (picH = picolinic acid, picOH = picolinic acidN-oxide). The complex [Th(dip)₂] · 3H₂O (dipH₂ = pyridine-2,6-dicarboxylic acid) is also reported. Thorium(IV) complexes of the types [Th(quin)₂] · 2H₂O and [Th(quind)₂(acac)₂] (quinH₂ = quinolinic acid or pyridine-2,3-dicarboxylic acid, quindH = quinaldinic acid) were prepared by the interaction of [Th(acac)₄] with the respective acids in acetone. The lower solubility and i.r. spectral studies of the complex [Th(quin)₂] · 2 H₂O suggest that it is polymeric.