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Caryolanes are known as typical plant-derived sesquiterpenes. Here we describe the isolation and full structure elucidation of three caryolanes, bacaryolane A–C (1–3), that are produced by a bacterial endophyte (Streptomycessp. JMRC:ST027706) of the mangrove plant Bruguiera gymnorrhiza.By 2D NMR, analysis of the first X-ray crystallographic data of a caryolane (bacaryolane C), CD spectroscopy, and comparison with data for plant-derived caryolanes, we rigorously established the absolute configuration of the bacaryolanes and related compounds from bacteria. Bacterial caryolanes appear as the mirror images of typical plant caryolanes. Apparently plant and bacteria harbor stereodivergent biosynthetic pathways, which may be used as metabolic signatures. The discovery of plant-like volatile terpenes in endophytes not only is an important addition to the bacterial terpenome but may also point to complex molecular interactions in the plant–microbe association.

A new synthesis of pushpull pyrroles of type 5was developed starting from bisimidoyl chlorides 1and various iminodiacetic acid derivatives 3. The use of appropriate Ntrifluoroacetyl residues as protectingactivating group proved to be the method of choice for the straightforward preparation of the 3,4diarylamino1Hpyrroles 5. When benzothiazole substructures are present in 2,5position of heterocycles 5, a twoelectron oxidation leads to 3Hpyrroles of type 6in excellent yields. However, in the case of cyano or ester groups, a further oxidative process immediately led to the new 3Hpyrrolo[3,4b]quinoxalines 7via intramolecular ring anellation. © WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009

The cyclization reactions between bisimidoylchlorides 1and ketones, which possess different CHacidity, were investigated. Diphenylacetone 2reacts under mild conditions viaC,Ocyclization of the preformed enolate to yield the iminofurane derivative 3. Upon treatment with trifluoroacetic acid, the latter can be rearranged quantitatively into the pyrrolone 5. In contrast, 1,3acetonedicarboxylate 9and cyclohexanone 12immediately lead to highly substituted pyrrolones 11and 14. Obviously, the primarily formed cyclization products undergo a very fast 1,3acyl rearrangement DimrothMummRearrangement. The structures of the maleiimide 11and the indolone 14were determined by single crystal Xray structure analysis. Due to its aminoimino substructure, compound 3is an efficient ligand for metal complexation reactions, exemplified by the synthesis of two different Zncomplexes 7and 8.

Depending on the substitution patterns in the sulfanes 1, two different types of thiophenes 3 and 4 can be obtained upon cyclization with a bis-imidoyl chloride 2. Whereas thiodiglycolic acid diester yielded a thiophene derivative with the expected symmetrical structure, thiodiacetonitrile gives a derivative with an asymmetrical substitution pattern (2,3-arylamino/4,5-dicyano). This unexpected finding was confirmed by single-crystal X-ray analysis and possibly originates from a 1,2-rearrangement of a thietanium salt intermediate. These new push-pull thiophenes are easily accessible in a single step from simple starting materials. Unlike in the case of the derivatives 3, the substitution pattern in 4 was not previously known. A simple hydrolysis of compounds 4 offers a new and efficient route to derivatives of thiomaleic acid anhydrides 6. The 2,3-dicyano-4,5-bis(arylamino)thiophenes 4 exhibit strong solvatofluorescence with unusually large Stokes shifts. Quantum chemical calculations explain the large Stokes shifts as most probably being due to strong structural relaxation upon excitation to the S1 state.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Oxazolidine vinyl oxirane 1, a novel and highly versatile building block for the preparation of enantiopure D-(+)-erythro-sphingosine and analogues, has been prepared by chloroallylboration of the Garner aldehyde with absolute stereocontrol and in good yield.

via two consecutive Henry nitroaldol reactions

The structures of the title compounds point to a common biosynthetic precursor.

The complex cycloaddition—ring transformation reaction of pyrido[1,2‐a]pyrazines (I) with substituted naphthoquinones is studied.

Two different pathways for the synthesis are investigated.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.