Anion receptors containing thiazine-1,1-dioxide heterocycles as hydrogen bond donors

• Hong-Bo Wang,
• James A. Wisner and
• Michael C. Jennings

Beilstein J. Org. Chem. 2010, 6, No. 50, doi:10.3762/bjoc.6.50

• installation of this subunit in a potential host. The solid-state structures of both newly synthesized receptors were confirmed by X-ray diffraction analysis of single crystals grown by the slow diffusion of isopropyl ether into concentrated DMSO solutions of each (Figure 3). Unfortunately, attempts to co

Acid catalyzed cyclodimerization of 2,2-bis(trifluoromethyl)-4-alkoxy-oxetanes and -thietanes. Synthesis of 2,2,6,6-tetrakis(trifluoromethyl)-4,8-dialkoxy-1,5-dioxocanes and 3,3,7,7-tetrakis(trifluoromethyl)-9-oxa-2,6-dithia-bicyclo[3.3.1]nonane

• Viacheslav A. Petrov and
• Will Marshall

Beilstein J. Org. Chem. 2010, 6, No. 46, doi:10.3762/bjoc.6.46

• was established by single crystal X-ray diffraction analysis (see Supporting Information File 2). Hydrocarbon oxetanes were reported to react with alcohols under relatively mild conditions [13]. It is interesting, that electron deficient oxetanes 1 also have similar reactivity and rapidly react with

• hexafluoroisopropanol (25 °C, 16 h, NMR) and both 4a and 4b were found to be inert towards BF3·OEt2 (25 °C, 10 h, CH2Cl2, NMR). However, the addition of compounds 4a or 4b to concentrated H2SO4 resulted in an exothermic reaction and formation of a product, which, after single crystal X-ray diffraction analysis, was

Synthesis and binding studies of two new macrocyclic receptors for the stereoselective recognition of dipeptides

• Ana Maria Castilla,
• M. Morgan Conn and
• Pablo Ballester

Beilstein J. Org. Chem. 2010, 6, No. 5, doi:10.3762/bjoc.6.5

• the formation of the peptide bonds of the macrocyclic structures, both receptors have been isolated as single diastereoisomers. The molecular structure of receptor 1 has been confirmed by single-crystal X-ray diffraction analysis. Although molecular modeling suggested that the cyclic receptors can

The enantiospecific synthesis of (+)-monomorine I using a 5-endo- trig cyclisation strategy

• Malcolm B. Berry,
• Donald Craig,
• Philip S. Jones and
• Gareth J. Rowlands

Beilstein J. Org. Chem. 2007, 3, No. 39, doi:10.1186/1860-5397-3-39

• epimeric pairs proved problematic due to difficulties encountered during separation, and the presence of overlapping signals in the 1H NMR spectrum. Finally, a combination of X-ray diffraction analysis and comparison of the 1H NMR showed that the major diastereoisomer in each case was the undesired C-5

Diastereoselective synthesis of some novel benzopyranopyridine derivatives

• Pradeep K. Mohakhud,
• Sujeet M. R. Kumar,
• Vasanth M. R. Kumar,
• Ravi M. R. Kumar,
• Moses D. R. Babu,
• Vyas D. R. K and
• Om D. R. Reddy

Beilstein J. Org. Chem. 2006, 2, No. 25, doi:10.1186/1860-5397-2-25

• determined as S,S by X-ray diffraction analysis (Figure 4) (For details see also: Figure 4 and Supporting Information File 1). Structure elucidation of 5b The mass spectrum of 5b displayed a molecular ion at m/z 245 corresponding to the molecular formula C14H15NO3. Interestingly the molecular ion is 18 amu