Microwave assisted organic synthesis-a review

Asymmetric 1,3-Dipolar Cycloaddition Reactions

Many fungi, lichens, and bacteria produce xanthones (derivatives of 9H-xanthen-9-one, “xanthone” from the Greek “xanthos”, for “yellow”) as secondary metabolites. Xanthones are typically polysubstituted and occur as either fully aromatized, dihydro-, tetrahydro-, or, more rarely, hexahydro-derivatives. This family of compounds appeals to medicinal chemists because of their pronounced biological activity within a notably broad spectrum of disease states, a result of their interaction with a correspondingly diverse range of target biomolecules. This has led to the description of xanthones as “privileged structures”.(1) Historically, the total synthesis of the natural products has mostly been limited to fully aromatized targets. Syntheses of the more challenging partially saturated xanthones have less frequently been reported, although the development in recent times of novel and reliable methods for the construction of the (polysubstituted) unsaturated xanthone core holds promise for future endeavors. In particular, the fascinating structural and biological properties of xanthone dimers and heterodimers may excite the synthetic or natural product chemist.

Xanthones from Fungi, Lichens, and Bacteria: The Natural Products and Their Synthesis

Herbicides with new modes of action (MOAs) are badly needed due to the rapidly evolving resistance to commercial herbicides, but a new MOA has not been introduced in over 20 years. The greatest pest management challenge for organic agriculture is the lack of effective natural product herbicides. The structural diversity and evolved biological activity of natural phytotoxins offer opportunities for the development of both directly used natural compounds and synthetic herbicides with new target sites based on the structures of natural phytotoxins. Natural phytotoxins are also a source for the discovery of new herbicide target sites that can serve as the focus of traditional herbicide discovery efforts. There are many examples of strong natural phytotoxins with MOAs other than those used by commercial herbicides, which indicates that there are molecular targets of herbicides that can be added to the current repertoire of commercial herbicide MOAs.

http://www.plantphysiol.org/content/plantphysiol/early/2014/04/30/pp.114.239061.full.pdf

Natural Compounds as Next Generation Herbicides

Xanthones from fungi, lichens, and bacteria : the natural products and their synthesis

Microbial transformation of diterpenes: Hydroxylation of sclareol, manool and derivatives by Mucor plumbeus

Saradaferin, a new sesquiterpenoid coumarin from Ferula assafoetida

Tracheobronchial amyloidosis is a rare manifestation of the disease and has never been described with FDG PET/CT. In this study, we report a case of a 70-year-old man with increasing dyspnea, a right pleural effusion, a tracheobronchial circumferential wall thickening, and a mediastinal fat infiltration on CT scan. FDG PET/CT revealed intense tracheobronchial uptake associated with mediastinal and intra-abdominal fat uptake. Bronchoscopy and mediastinoscopy with biopsies confirmed the diagnosis of primary amyloidosis and excluded malignancy. FDG PET/CT could be useful for the evaluation of tracheobronchial amyloidosis metabolic activity and follow-up.

Tracheobronchial FDG uptake in primary amyloidosis detected by PET/CT.

Facial Selectivity in Cycloadditions of a Chiral Ketene Acetal under Microwave Irradiation in Solvent-Free Conditions. Configurational Assignment of the Cycloadducts by NOESY Experiments and Molecular Mechanics Calculations

Alain Neuman

Papers

Microbial transformation of diterpenes: Hydroxylation of sclareol, manool and derivatives by Mucor plumbeus

Saradaferin, a new sesquiterpenoid coumarin from Ferula assafoetida

Tracheobronchial FDG uptake in primary amyloidosis detected by PET/CT.

Facial Selectivity in Cycloadditions of a Chiral Ketene Acetal under Microwave Irradiation in Solvent-Free Conditions. Configurational Assignment of the Cycloadducts by NOESY Experiments and Molecular Mechanics Calculations

Structure cristalline de la 2-acétamido-1-N-(l-aspart-4-oyl)-2-désoxy-β-d-glucopyranosylamine