Design, synthesis and structure-bactericidal activity relationships of novel 9-oxime ketolides and reductive epimers of acylides was written by Tian, Jing-Chao;Han, Xu;Lv, Wei;Li, Ya-Xin;Wang, Hui;Fan, Bing-Zhi;Cushman, Mark;Liang, Jian-Hua. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2017.Category: ethers-buliding-blocks This article mentions the following:
Erythromycin was long viewed as a bacteriostatic agent. The erythromycin derivatives, 9-oxime ketolides have a species-specific bactericidal profile. Among them, the 3′-allyl version of the 9-oxime ketolide is bactericidal against Streptococcus pneumoniae and Streptococcus pyogenes. In contrast, the 2-fluoro analogs show bactericidal activities against S. pneumoniae, Staphylococcus aureus and Moraxella catarrhalis, while the 2-fluoro analogs are only bactericidal against S. pneumoniae and Haemophilus influenzae. Reduction of the ketolides led to novel epi-acylides, the 3-O-epimers of the acylides. Alteration of linker length, 2-fluorination and incorporation of addnl. spacers at the 9-oxime or 6-OH did not restore the epi-acylides back to be as active as the acylide. Mol. docking suggested that epimerization at the 3-position reshapes the orientation of the 3-O-side chain and leads to considerably weaker binding with bacterial ribosomes. In the experiment, the researchers used many compounds, for example, 1,1-Diisopropoxycyclohexane (cas: 1132-95-2Category: ethers-buliding-blocks).
1,1-Diisopropoxycyclohexane (cas: 1132-95-2) belongs to ethers. Ether is less polar than esters, alcohols or amines because of the oxygen atom that is unable to participate in hydrogen bonding due to the presence of bulky alkyl groups on both sides of the oxygen atom. But ether is more polar than alkenes. The unique properties of ethers (i.e., that they are strongly polar, with nonbonding electron pairs but no hydroxyl group) enhance the formation and use of many reagents. For example, Grignard reagents cannot form unless an ether is present to share its lone pair of electrons with the magnesium atom. Complexation of the magnesium atom stabilizes the Grignard reagent and helps to keep it in solution.Category: ethers-buliding-blocks
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem