36669-06-4

The pH dependence of the condensation of dimethyl 3-oxoglutarate and malondialdehyde to produce 2,6-bis(methoxycarbonyl)phenol and tetramethyl 3,7-dihydroxybicyclonona-2,6-diene-2,4,6,8-tetracarboxylate has been studied in detail: the yield of the former is maximal at pH 4,5, the latter at pH 7.5.The hydrolysis-decarboxylation of the latter provides a convenient route to bicyclononane-3,7-dione.The mechanism proposed for this reaction of malonodialdehyde is also relevant to the chemistry of glyoxal and dimethyl 3-oxoglutarate.The retrosynthetic analysis of the bicyclononane skeleton is considered from a topological perspective.

Transmembrane channels formed by functionalized hydrazide macrocycles are reported. The different pH values of buffer solutions have a significant effect on the K+/Cl- selectivity of the macrocycles. This unique transport behavior is

A route to the direct amidation of aromatic-ring-tetheredN-carbamoyl tetrahydroisoquinoline substrates was developed. This route enabled general access to 8-oxoberberines and their 5- and 7- membered C-ring homologues. It overcomes the undesired tandem side-reactions that result in the destruction of the isoquinoline backbone, which inevitably occurred under our previously reported superacidic carbamate activation method.

The cytotoxicity of the antitumor drug BLM is believed to be related to the ability of the corresponding iron complex (Fe-BLM) to engage in oxidative double-strand DNA cleavage. The iron complex of the ligand N4Py (Fe-N4Py; N4Py = N,N-bis(2-pyridyl)-N-bis

Described are ortho carboxy phenol derived acetals and compositions containing ortho carboxy phenol derived acetals which are useful for delivering biologically active compounds to cells. The acetals can be used to reversibly link up to three different mo

Benzamidine derivatives of formula (I) or pharmaceutically acceptable salts thereof exhibit excellent inhibitory activity against factor Xa and are useful for treating or preventing blood coagulation disorders: wherein R 1represents a hydrogen atom, a halogen atom, an alkyl group or a hydroxyl group; R 2represents a hydrogen atom, a halogen atom or an alkyl group, R 3represents a hydrogen atom, an optionally substituted alkyl group, an aralkyl group, an optionally substituted alkanoyl group or an optionally substituted alkylsulfonyl group, R 4and R 5 are the same as or different from each other and each represent a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group or an optionally substituted carbamoyl group, and R 6represents a substituted pyrrolidine group or substituted piperidine group.

The present invention relates to a nucleoside having the formula: STR1 where R1 is a hydrogen or a protecting group; R2 is a hydrogen or a coupling group; R3 and R4 are each either a hydrogen or an alkyl group, where R3 and R4 can be connected in a ring; R5 is a hydrogen, an alkyl group, or a carboxylic ester group; R6 is a hydrogen, an alkyl group, or a carboxylic ester group; R7 is a hydrogen, a nitro group, a halogen, a cyano group, or an alkyl group, where R7 is attached at either position 4, 5 or 6; and Base is a protected heterocyclic base. Further, the present invention relates to a method of making the nucleoside and a method of oligomer synthesis utilizing the nucleoside.

The sodium salt of dimethyl 1,3-acetonedicarboxylate (1) readily reacts with certain alkynals under mild conditions in THF to give a tetrasubstituted aromatic ring with regiocontrol at the metaposition through a Michael addition-aldol cyclization sequence. Thus the reaction of I with propynal, 2-butynal, 2-pentynal, 2-octynal, 4-(benzoyloxy)-2-butynal, and 4-((tetrahydropyranyl)-oxy)-2-butynal at 25 °C gave the following products: dimethyl 2-hydroxybenzene-1,3-dicarboxylate (11percent), dimethyl 2-hydroxy-4-methylbenzene-1,3-dicarboxylate (45percent), dimethyl 4-ethyl-2-hydroxybenzene-1,3-dicarboxylate (46percent), dimethyl 2-hydroxy-4-pentylbenzene-1,3-dicarboxylate (42percent), dimethyl 2-hydroxy-4-((pivaloyloxy)methyl)benzene-1,3-dicarboxylate (88percent), dimethyl 2-hydroxy-4-((benzoyloxy)methyl)benzene-1,3-dicarboxylate (74percent), and dimethyl 2-hydroxy-4-(((tetrahydropyranyl)oxy)methyl)benzene-1,3-dicarboxylate (70percent).

The hydrolysis of 3-carboxyaspirin (1) was kinetically investigated in the presence or absence of tri- or divalent metal ions.The spontaneous hydrolysis of the neutral and the monoanionic forms of 1 involves anhydride intermediates formed by the nucleophi

Reactions of the enaminones 1 with dimethyl 3-oxoglutarate in the presence of KF-AcOH or AcONa-AcOH and 18-crown-6 gave the dimethyl 2-hydroxy-1,3-benzenedicarboxylates 3, providing a new aromatic annelation reaction.Keywords - enaminone; dimethyl 3-oxoglutarate; buffer catalysis; aromatic annelation; dimethyl 2-hydroxy-1,3-benzenedicarboxylate

The enamine aldehydes RC(=CHNMe2)CHO (R = Et or Ph) were condensed with the bis-enolate CH2=C-(O-)CH=C(O-)OEt to give the title aromatic compounds.Thus these products are available from the acetals R1CH2CH(OR2)2 (R1 = R2 = Et; R1 = Ph, R2 =Me) in two steps.The Vilsmeier formylation of the several derivatives of butanal was examined.

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Glyoxal and dimethyl 3-oxoglutarate condense at pH nonane-2,4,6,8-tetracarboxylate.