Highly Efficient and Selective Deprotection Method for Prenyl, Geranyl, and Phytyl Ethers and Esters Using Borontrifluoride–Etherate

Design, Synthesis, Docking Studies and Monoamine Oxidase Inhibition of a Small Library of 1-acetyl- and 1-thiocarbamoyl-3,5-diphenyl-4,5-dihydro-(1H)-pyrazoles

“…Purification by column chromatography on silica gel (ethyl acetate: n -hexane 1:4) gave the title compounds. Characterization data obtained for compounds A3 – A5 and A7 were in accordance with [26], while for compound A6 were in accordance with [23].…”

“…In particular, 4-hydroxyacetophenone was reacted with different brominated compounds in order to obtain derivatives containing: (i) linear alkyl chain with increasing dimensions ( A1 – A5 ), (ii) unsaturated alkyl chain ( A6 ) and (iii) unsaturated/branched alkyl chain ( A7 – A8 ). Acetophenones A1 – A2 were commercially available, while the syntheses of A3 – A8 were performed in acetone at room temperature, in the presence of dried potassium carbonate [23]. The so obtained acetophenones were used for the next Claisen–Smith condensation reaction (Scheme 1, II ).…”

Streamlined One‐Pot Synthesis of Nitro Fatty Acids

“…Considering these aspects, we deemed the prenyl (Pre, 3-methylbut-2-en-1yl) protecting group as ideal choice for our purposes. It can be easily introduced using readily available prenol (3-methyl-2buten-1-ol), is stable towards (mild) bases and undergoes facile cleavage upon treatment with I 2 , DDQ, [21] or acids [22][23][24] in the presence of other sensitive functional groups.…”

Microwave-Promoted Deprenylation: Prenyl Ether as a Thermo­labile Phenol Protecting Group

“…If the multiplicities of the NMR signals were too complex to allow extraction of all coupling constants, the signals are denoted as 'dm' or 'tm', and only those coupling constants are noted which could be reliably determined. 13 C NMR spectra were recorded at 75 MHz, with a Bruker ARX-300 spectrometer, in CDCl 3 with CDCl 3 (δ = 77.0 ppm) as an internal standard, or in C 6 D 6 with C 6 D 6 (δ = 128.0 ppm) as an internal standard. IR spectra were recorded as ATR-FTIR spectra on a Perkin-Elmer UATR-Two spectrometer.…”

“…2 Gigg reported in an early publication that prenyl ethers are not isomerized to enol ethers by Wilkinson's catalyst, which makes them orthogonal to allyl ethers, but that the action of strong bases induces the formation of isoprene and the alkoxide. 7 Prenyl ethers are stable under mildly acidic conditions, 8 but can be cleaved with Lewis acids in the presence of nucleophiles, [9][10][11][12][13] oxidizing reagents, 14,15 radical-generating reagents 16,17 or palladium catalysts in the presence of C-nucleophiles. 18 We have explored prenyl ethers as thermolabile protecting groups in the course of a project directed at the synthesis of allylated and prenylated flavonoids 19,20 and coumarins.…”