Josefa Anaya

Furanoeremophilane derivatives from Senecio flavus

The aerial parts of Senecio flavus contain besides known eremophilane derivatives, four new furanoeremophilanes oxidized at C-3 and a new eremophilenone lactam. The rhizomes of the plant also contain the same ketoeremophilenes found in the aerial parts and a new epoxyeremophilanolide. The structure of these compounds has been established by spectroscopic methods.

New enantioselective synthesis of 4-hydroxy-2-oxopyrrolidine-N-acetamide (oxiracetam) from malic acid

Abstract The enantioselective synthesis of oxiracetam has been accomplished from readily available optically active D(+) and L(−) malic acids. The key step of the described method involves the selective reduction of a chiral cyclic diimide; in this way, both enantiomers of 4-hydroxy-2-oxopyrrolidine-N-acetamides were prepared.

Composition and Antimicrobial Activity of Ammoides pusilla (Brot.) Breistr. Essential Oil

Abstract The essential oil of the aerial parts of Ammoides pusilla was analyzed using both GC and GC/MS. The results revealing no less than 46 constituents among which thymol (44.5%), γ-terpinene (32.9%) and p-eymene (13.5%) were the most abundant. The antimicrobial activity of A. pusilla oil was studied using the agar diffusion test on eight strains of bacteria, and against fungus and yeast. The two-fold oil solution showed an important antimicrobial activity against Serratia marcescens, Salmonella enteritidis, Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Staphyhloccus aureus (ATCC 25923), Klebsiella pneumoniae, Pseudomonas syringae pv. syringae, Pseudomonas syringae pv. mosprunorum, Aspergillus niger and Candida albicans.

Improved receptors for dibutylmalonic acid

Abstract New molecular receptors with a dibenz[c,h]acridine skeleton bearing functional groups complementary to dibutylmalonic acid have been developed.

A lupeol derivative from Salvia pratensis

Abstract The aerial parts of Salvia pratensis afforded, in addition to the known triterpenoids β-amyrin, germanicol, lupeol and loranthol, a new related lupenol, 7β-hydroxylup-20(29)-en-3-one, whose structure was elucidated by spectroscopic methods and chemical transformations.

Secondary metabolites from Senecio minutus and Senecio boissieri: a new jacaranone derivative

Jacaranone (1), the related new dimethoxy derivative 2, and known triterpenoids were isolated from the aerial parts of Senecio minutus. The aerial parts and the rhizomes of Senecio boissieri afforded the furanoeremophilanes 3 and 4 and known triterpenoids.

Four aliphatic esters of Chamaemelum fuscatum essential oil

Abstract Four new aliphatic esters were isolated from the essential oil of Chamaemelum fuscatum . Three are esters of methacrylic acid with 2-methyl-2 E -butenol, 2-hydroxy-2-methyl-3-butenol and 2-hydroxy-2-methyl-3-oxobutanol. The other is neryl isovalerate obtained in addition to known compounds. The structures were determined by spectral measurements and by synthesis.

Different approaches to the asymmetric synthesis of 1,3,6-trisubstituted and 1,2,3,6-tetrasubstituted carbapenems1 from D-glucosamine

Abstract Different stereocontrolled syntheses of optically active 1,3,6-trisubstituted and 1,2,3,6-tetrasubstituted carbapenems 1 are reported. D -glucosamine, as chiral auxiliary, trans -cinnamaldehyde and methoxyacetyl chloride were used as starting materials in the Staudinger ketene-imine monobactam formation. Radical cyclization and oxidation reactions led to the desired carbapenems.

The use of radical decarboxylation in the preparation of 1-methylcarbapenem antibiotic precursors from D-glucosamine

Abstract The stereocontrolled synthesis of optically active 1-methylcarbapenams has been performed by radical cyclization and radical decarboxylation. 1,3,4-Trisubstituted-2-azetidinones, prepared by the Staudinger reaction with D -glucosamine as chiral auxiliary and sorbic acid were used as starting materials.

Chromenone derivatives as receptors for N-benzoylamino acids

The chromenone derivative 5, easy to synthesize from 2-hydroxyacetophenone 1, has been used to prepare the hosts 7–10 and 12. These combine three hydrogen bonds, π-stacking and chargetransfer interactions for the complexation of N-benzoylamino acids in CDCl3.