1.Synthesis of new monodentate spiro phosphoramidite ligand and its application in Rh-catalyzed asymmetric hydrogenation reactions.
Wu S1, Zhang W, Zhang Z, Zhang X. Org Lett. 2004 Sep 30;6(20):3565-7.
[reaction: see text] A new spirocyclic diol, 9,9'-spirobixanthene-1,1'-diol, was synthesized in two steps from readily available starting material m-phenoxyanisole. Resolution of the racemic diol was achieved by cocrystallization with N-benzylcinchonidinium chloride and N-benzylquininium chloride in acetonitrile. The corresponding spiro monodentate phosphoramidite ligand has been prepared for Rh-catalyzed asymmetric hydrogenation of alpha-dehydroamino acid derivatives and itaconic acid with excellent enantioselectivities (up to >99% ee).
2.Application of a mathematical topological pattern of antihistaminic activity for the selection of new drug candidates and pharmacology assays.
Duart MJ1, García-Domenech R, Galvez J, Aleman PA, Martín-Algarra RV, Antón-Fos GM. J Med Chem. 2006 Jun 15;49(12):3667-73.
Molecular topology was used to achieve a mathematical model capable of classifying compounds according to their antihistaminic activity and low sedative effects. By application of this model of activity to databases containing chemical reagents and drugs exhibiting other pharmacological activity, we selected 30 compounds with possible antihistaminic activity. After those with possible sedative effects were discarded, activity tests were performed with five chemical reagents and three drugs searching for in vivo antihistaminic activity. The obtained results indicate that compounds such as 4-[(E)-2-(1,3-benzothiazol-2-yl)vinyl]-N,N-dimethylaniline (AH2), 2-ethyl-9,10-dimethoxyanthracene (AH4), and 2,4-bis(alpha,alpha-dimethylbenzyl)phenol (AH5) showed antihistaminic activity above terfenadine, the reference drug, whereas others, for instance, pergolide, miconazole, trihexyphenidyl, 2-(dibenzylamino-3-phenyl-1-propanol (AH1), and N-benzylquininium chloride (AH3), were less active than terfenadine.
3.Practical synthesis of chiral 9,9'-spirobixanthene-1,1'-diol.
Zhang W1, Wu S, Zhang Z, Yennawar H, Zhang X. Org Biomol Chem. 2006 Dec 21;4(24):4474-7. Epub 2006 Nov 9.
A concise four-step synthesis of 9,9'-spirobixanthene-1,1'-diol is reported, featuring a practical preparation at large scale without the use of column chromatography purification. Co-crystallization with N-benzylcinchonidinium chloride and N-benzylquininium chloride rendered the optically pure product in both enantiomers.
4.Different enantioselective interaction pathways induced by derivatized quinines.
Uccello-Barretta G1, Balzano F, Quintavalli C, Salvadori P. J Org Chem. 2000 Jun 16;65(12):3596-602.
The stereochemistries in solution of the diastereoisomeric complexes formed by quinines modified at the hydroxyl site (9-O-acetylquinine; 9-O-(3,5-dimethoxyphenylcarbamate)quinine) or quinuclidine nitrogen (N-benzylquininium chloride) and each enantiomer of 2-(3', 5'-dinitrobenzamido)-1-phenylethanol have been compared to those of the free compounds by (1)H NMR investigations. Completely different interaction models, also involving changes of the free state conformations, have been obtained.
