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The detection of reactive oxygen species (ROS) in biological systems and its imaging is of great importance. Among them, the hydroxyl radical ( OH) stands out as one of the most reactive, playing an important role in many physiological and pathological processes. Here we report a two-photon (TP) turn-on fluorescent probe with good selectivity and sensitivity towards OH. The molecular design of this naphthalene-indoline compound enables it to accurately target lysosomes in its non-fluorescent (“off”) state, where interaction with OH gives rise to the fluorescent (“on”) state and allows for the imaging of OH generation in living mouse embryonic fibroblast (MEF) cells. The present study provides an approach for improving our understanding of the role of OH in biological processes.

In vitro drug allergy tests have limited sensitivity, partly due to a poor understanding of the immunological recognition of in vitro drug-protein conjugates. We have designed and synthesized multivalent mono- and bi-epitope dendrimeric antigen (DeAn) conjugates and studied their chemical and tridimensional structures. We describe differences in the spatial distribution and conformation of these conjugated epitopes for the first time: a partially hidden benzylpenicilloyl and a more exposed amoxicilloyl. Our data suggest that DeAn conjugates provide a useful model for studying IgE recognition in patients who suffer from an allergic reaction to benzylpenicillin and/or amoxicillin. 1D and 2D NMR, MDS and immunochemical studies provide evidence that both antigen composition and tridimensional distribution play key roles in IgE-antigen recognition. Bi-epitope DeAn conjugates could potentially allow the diagnosis of patients allergic to any of these two drugs with a single test and represent the basis for a broadly-applicable in vitro assay. From the clinical editor: The prevalence of allergic drug reactions is rising and there is an imperative need to identify patients at risk. In this interesting and important article, the authors developed a novel method for detecting drug specific IgE antibodies, responsible for allergic reactions, by using multivalent mono- and bi-epitope Dendrimeric Antigen (DeAn) conjugates. The continued success of this research may pave way of eventual development of a simple diagnostic test.

We report a flexible approach to the total synthesis of 4,5-dioxoaporphines based on the palladium(0) catalyzed Suzuki cross-coupling of phenylboronic acids with sterically hindered 2-bromo phenyl acetates or bromo phenyl acetamides, followed by sequential bicyclization of biarylacetamides promoted by oxalyl chloride/Lewis acid. The reduction of 4,5-dioxoaporphines provides a chemoselective entry to aporphines, dehydroaporphines and 4-hydroxy-dehydroaporphines. A three-steps total synthesis for (±)-O,O′-dimethylapomorphine from readily accessible precursors is also reported.

The amounts of sinoacutine, glaucine and protopine were used to identify three phytochemical groups from the six known populations of Platycapnos saxicola Willk. A combination of GC/MS and 1 H-NMR have been used for the identification and quantitation of

In continuation of our chemical studies on the Andalusian Flora (Valpuesta et al., 1995, 1999; Suau et al., 1998, 2002), we focused on the genus Senecio in our search for pyrrolizidine alkaloids (PAs). We collected three endemic species, viz. Senecio elodes Boiss. ex DC. (MGC 25920) and S. granatensis Boiss. (MGC 20646) from Sierra Nevada (Granada, Spain), and S. malacitanus L. (MGC 30068) from El Pantano del Agujero (Malaga, Spain). Voucher specimens are deposited at the Herbarium of the Department of Botany of the University of Malaga (MGC).

We describe herein a new synthesis of enantiopure alkylidene 1,1-bis-p-tolyl-sulfoxides (5), based on a two-steps sequence. The first one involves the alkylation of the lithium anion of the (S,S)-bis-p-tolylsulfinylmethane (1) with aldehydes. The second one consists in a mild dehydration of the sulfinyl alcohols 3 and 4 with the morpho CDI reagent. Some features (reactivity, diastereoselectivity) of the alkylation reaction are discussed.

The Polonovski–Potier reaction of trans and cis berbines N-oxides was studied. The 8-cyano derivative obtained from transN-oxides were used to synthesize 8-hydroxymethyl and 8-methyl berbines. This procedure was applied to the stereocontroled synthesis of (8R, 14S)-(−)-8-methylcanadine from (14S)-(−)-canadine.

The direct insertion of a hydroxymethyl group at position C-8 in a protoberberinium ion by photoaddition of methanol was approached via two mechanistic pathways: acetone-sensitized and single-electron transfer. The latter produces 8-hydroxymethylberbines in good yields after reduction. By combining this photochemical reaction with the oxidation of the photoproduct, syntheses of (±)-solidaline and its C-13 epimer from palmatine chloride were accomplished for the first time. On the other hand, insertion of a hydroxymethyl group at position 14 of the berberine skeleton in order to open a synthetic pathway for zijinlongine proved unsuccessful.

Sixteen isoquinoline alkaloids were isolated from Berberis vulgaris subsp. australis . In addition to quaternary protoberberines and bisbenzylisoquinolines, a new seco - bis benzylisoquinoline, (-)-tejedine, is reported.

The introduction of a hydroxymethyl group at the C-8 position of berberinium salts was readily achieved by photoaddition of methanol. The resulting photoproducts were isolated as tetrahydroprotoberberine derivatives. By combining this photochemical reaction with the oxidation of the photoproduct, the synthesis of (±)-solidaline starting from palmatine chloride was accomplished for the first time.

The plants of genus Fumaria L., which encompasses about 40 species (Southon and Buckingham, 1989), are annual herbs which have a wide distribution from India to Macaronesia. Twenty-two species are restricted to the Ibero-Mauritanian Region, which includes Algeria, Morocco and Spain (Liden, 1986). Plant material of Fumaria agraria Lag. (Fumariaceae) was collected from Churriana (Malaga, Spain) and that of Fumaria sepium Boiss. (Fumariaceae) from Los Barrios (Cadiz, Spain). Both were identified by the Department of Botany of the Faculty of Sciences of the University of Malaga. Voucher specimens (F. agraria MGC-23062 and, F. sepium MGC-31528) are deposited in the Faculty’s herbarium.