A series of bicyclic nucleosides containing a triazolyl-carbohydrate moiety were synthesized and their antitumor activity in vitro for human cancer cell lines was also tested. Compound 11 was synthesized efficiently with 3,6-anhydro sugar 7 as raw material, while compound 7 was prepared from 1,2;5,6-di-O-isopropylidene-α-d-glucose. Compounds 12a-e were synthesized by treating compound 11 with a...

Partial deprotonation of the bicyclic guanidine 1,4,6-triazabicyclo[3.3.0]oct-4-ene (Htbo) is achieved using (n)BuLi. Isolation of the resulting lithium salts has resulted in the structural characterization of the mixed anion complex {[Li(tbo)(VIII)(tboH)](2)}(infinity) (where -H = 1-(2-aminoethyl)-2-imidazolidinethione) and the partially deprotonated salt Li(6)(tbo)(6)(Htbo)(3), 1b. The neutra...

Members of the catechol diether class are highly potent non-nucleoside inhibitors of HIV-1 reverse transcriptase (NNRTIs). The most active compounds yield EC50 values below 0.5 nM in assays using human T-cells infected by wild-type HIV-1. However, these compounds such as rilpivirine, the most recently FDA-approved NNRTI, bear a cyanovinylphenyl (CVP) group. This is an uncommon substructure in d...

Let ∆(G), ∆ for short, be the maximum degree of a graph G. In this paper, trees (resp., unicyclic graphs and bicyclic graphs), which attain the first and the second largest spectral radius with respect to the adjacency matrix in the class of trees (resp., unicyclic graphs and bicyclic graphs) with n vertices and the maximum degree ∆, where ∆ ≥ n+1 2 (resp., ∆ ≥ n 2 +1 and ∆ ≥ n+3 2 ) are determ...

Attempted oxidation of a TADDOL-derived bisthioacetate resulted in a rather unexpected and remarkable cyclization and deprotection reaction, giving a thiolane-1, 1-dioxide as the main product. Systematic in situ ESI-HRMS studies revealed a bicyclic, highly acid labile key intermediate of this reaction. Supported by force field calculations, the high sensitivity of this intermediate was judged t...

New compounds with carbohydrate-similar structure (carbohydrate mimetics) are presented in this article. Starting from enantiopure nitrones and lithiated TMSE-allene we prepared three 1,2-oxazine derivatives which underwent a highly stereoselective Lewis acid-induced rearrangement to give bicyclic products in good yield. Subsequent reductive transformations delivered a library of new poly(hydro...

Tetrasubstituted pyrrolidines representing analogs of homoproline were synthesized by three-component condensation of aryl(heteroaryl)aldehydes, asparagine and N-methylmaleimide (NMM). Compounds with (1S*, 3R*, 3aS*, 6aR*)-configuration at the corresponding carbon positions of the bicyclic pyrrolidine ring could be isolated ona preparative scale.

Chemical stabilities of six low-energy isomers of C24 derived from global-minimum search are investigated. The six isomers include one classical fullerene (isomer 1) whose cage is composed of only five- and six-membered rings (56-MRs), three nonclassical fullerene structures whose cages contain at least one four-membered ring (4-MR), one plate, and one monocyclic ring. Chemical and electronic p...