European journal of medicinal chemistry, 44(9), 3746-3753 (2009-05-08)
New N-acetyl (5-8) and N-thiocarbamoyl (9-12) derivatives of 4,5-dihydropyrazole were synthesized starting from alpha,beta-unsaturated ketones under the effect of hydrazine hydrate and thiosemicarbazide, respectively. N-Thiocarbamoylpyrazole derivatives (9-12) were cyclized using either ethyl bromoacetate or phenacyl bromides to afford the novel
Three protected derivatives of 1,N(6)-ethenoadenine nucleosides, viz. 3-[5-O-(4,4'-dimethoxytrityl) of 7-formyl-(1) and 7-(1,2-diacetyloxypropyl)-2'-deoxyadenosine (2), and 3-[5-O-(4,4'-dimethoxytrityl)-2-O-(tert-butyldimethylsilyl)-7-(ethoxycarbonyl)adenosine (3), expected to allow introduction of formyletheno and carboxyethenoadenine adducts into oligonucleotides by the conventional phosphoramidite chemistry, have been synthesized.
Chemistry, an Asian journal, 6(8), 2130-2146 (2011-05-21)
Vanol is a member of the vaulted biaryl family of ligands and it has been proven to be very effective in a number of asymmetric catalytic reactions. The previous synthesis of vanol, while effective, is limited by the cost of
Peptide nucleic acids (PNAs) make a promising group of DNA analogues. The backbone of typical PNA oligomers is composed of N-(2-aminoethyl)glycine units, linked by the peptide bonds. The backbone secondary amine groups are acylated with carboxyalkyl derivatives of nucleobases. One
Reformatsky reaction of 3beta, 21-diacyloxy-and 3beta-methoxy-21-acyloxy-5-pregnen-20-one with ethyl bromoacetate yields, through an intramolecular 1,2-acyl migration, 38, 20 XI-acyloxy-14alpha-card-5-enolides were converted into the respective 20 XI-hydroxy-14alpha-card-5-enolides and the 14 alpha-carda-5,20(22)-dienolides. Experimental support to the proposed intramolecular 1,2-acyl migration is provided by
