A case of meningitis due to Achromobacter xylosoxidans denitrificans 60 years after a cranial trauma.

BACKGROUND: Achromobacter xylosoxidans (AX) is a non-fermentative aerobic gram-negative bacillus. It is an opportunistic pathogen and the causative agent of various infections. We report an original case of late posttraumatic meningitis due to AX denitrificans. CASE REPORT: An 83-year-old man was hospitalized for acute headache, nausea and vomiting. The emergency brain computer tomography (CT) scan did not reveal any anomaly. In his medical history, there was an auditory injury due to a cranial trauma incurred in a skiing accident 60 years earlier. Cytobiochemical analysis of the cerebrospinal fluid (CSF) revealed increased levels of neutrophils and proteins. The CSF bacterial culture was positive: the Gram stain showed a gram-negative bacillus, oxidase + and catalase +, and the biochemical pattern using the API 20 NE strip revealed AX dentrificans. Late posttraumatic meningitis on a possible osteomeningeal breach was diagnosed even though the breach was not confirmed because the patient declined a second brain CT scan. The patient was successfully treated with meropenem. CONCLUSIONS: This report demonstrates the importance of searching for unusual or atypical organisms when the clinician encounters meningitis in a particular context, as well as the importance of adequate follow-up of craniofacial traumas.

Ynamides: versatile tools in organic synthesis.

Ynamides display an exceptionally fine balance between stability and reactivity. They also offer unique and multiple opportunities for the inclusion of nitrogen-based functionalities into organic molecules, and are emerging as especially useful and versatile building blocks for organic synthesis. Recent breakthroughs in the preparation of these substrates have revitalized interest in nitrogen-substituted alkynes, and the beginning of the 21st century has witnessed an ever-increasing number of publications reporting the development of new reactions or synthetic sequences starting from ynamides. This Review highlights major developments in this area.

Copper-catalyzed cyclization reactions for the synthesis of alkaloids.

Copper-mediated Ullmann type transformations have recently evolved as useful and valuable synthetic tools in organic synthesis. If newly developed catalytic systems are readily available, inexpensive, and tolerate most functional groups, they also provide new opportunities in natural product synthesis since they allow new and efficient retrosynthetic disconnections. They are also especially convenient for the development of straightforward cyclization and macrocyclization procedures. The present article showcases some examples of copper-catalyzed cyclization reactions for the synthesis of alkaloids we have recently developed.

Copper-mediated coupling of 1,1-dibromo-1-alkenes with nitrogen nucleophiles: a general method for the synthesis of ynamides.

Mild reaction conditions are the advantage of the title reaction, which allows straightforward entry to a variety of ynamides starting from readily available 1,1-dibromo-1-alkenes, which act as attractive alkynylating agents (see scheme; EWG = electron-withdrawing group, DMF = N,N-dimethylformamide).

Direct C-glycosylation by indium-mediated alkynylation on sugar anomeric position.

Indium-mediated alkynylation reaction was studied for the direct preparation of C-glycosides. Easily available starting sugar derivatives with an acetyl group at the anomeric position were tested as electrophiles toward alkynylindium reagents under Barbier conditions. Good yields and stereoselectivities were observed during the reaction. The alkynylation was applied to the synthesis of an alpha-(1-->6)-C-disaccharide analogue of isomaltoside.

A convergent synthesis of the fully elaborated macrocyclic core of TMC-95A.

A concise and straightforward synthesis of the fully elaborated macrocyclic core of TMC-95A is reported. A highly efficient organocatalyzed aldolization between isatin and dihydroxyacetone derivatives and formation of the biaryl subunit with concomitant macrocyclization are the characteristic features of this synthesis.

Concise Total Synthesis of (+)-Bionectins A and C.

The concise and efficient total synthesis of (+)-bionectins A and C is described. Our approach to these natural products features a new and scalable method for erythro-ß-hydroxytryptophan amino acid synthesis, an intramolecular Friedel-Crafts reaction of a silyl-tethered indole, and a new mercaptan reagent for epipolythiodiketopiperazine (ETP) synthesis that can be unravelled under very mild conditions. In evaluating the impact of C12-hydroxylation, we have identified a unique need for an intramolecular variant of our Friedel-Crafts indolylation chemistry. Several key discoveries including the first example of permanganate-mediated stereoinvertive hydroxylation of the α-stereocenters of diketopiperazines as well as the first example of a direct triketopiperazine synthesis from a parent cyclo-dipeptide are discussed. Finally, the synthesis of (+)-bionectin A and its unambiguous structural assignment through X-ray analysis provides motivation for the reevaluation of its original characterization data and assignment.

Synthesis of ketene N,N-acetals by copper-catalyzed double-amidation of 1,1-dibromo-1-alkenes.

An efficient procedure for the preparation of ketene N,N-acetals by copper-catalyzed double amidation of 1,1-dibromo-1-alkenes is reported. The reaction was found to be general, and ketene aminals could be obtained in good yields when potassium phosphate in toluene was used at 80 degrees C. The reaction was found to proceed through a regioselective monocoupling reaction followed by dehydrobromination and hydroamidation.

Copper-catalyzed cyclization of iodo-tryptophans: a straightforward synthesis of pyrroloindoles.

Pyrroloindoles are a key structural motif found in a wide number of biologically active alkaloids. Intramolecular copper-catalyzed coupling of readily accessible 2-iodo-tryptophan derivatives occurs in excellent yield, affording a wide range of polysubstituted, enantioenriched tetrahydropyrrolo[2,3- b]indoles. Diketopiperazines are also suitable substrates for this cyclization reaction, which affords a straightforward entry to tetra- to hepta-polycyclic systems.