1211-57-0

Upstream product

• 687-47-8 (S)-Ethyl lactate 
• 98-88-4 benzoyl chloride 
• 65-85-0 benzoic acid 
• 100-39-0 benzyl bromide 

Downstream Products

• 889-65-6 ethyl 3-hydroxy-2,3-dimethyl-5-phenylpentanoate 
• 39922-60-6 ethyl 2-(1-hydroxycyclohexyl)propionate 

Relevant academic research and scientific papers

Luquilloamides, Cytotoxic Lipopeptides from a Puerto Rican Collection of the Filamentous Marine Cyanobacterium Oscillatoria sp.

Luquilloamides A–G (1–7) were isolated from a small environmental collection of a marine cyanobacterium found growing on eelgrass (Zostera sp.) near Luquillo, Puerto Rico. Structure elucidation of the luquilloamides was accomplished via detailed NMR and MS analyses, and absolute configurations were determined using a combination of advanced Mosher’s method, J-based configuration analysis, semisynthetic fragment analysis derived from ozonolysis, methylation, Baeyer–Villiger oxidation, Mosher’s esterification, specific rotations, and ECD data. Except for 2, the luquilloamides share a characteristic tert-butyl-containing polyketide fragment, β-alanine, and a proposed highly modified polyketide extension. While compound 1 is a linear lipopeptide with two α-methyl branches and a vinyl chloride functionality in the polyketide portion, compounds 4, 6, and 7 possess a cyclohexanone structure with methylation on the α- or β-positions of the polyketide as well as an acetyl group. Interestingly, the absolute configuration at C-5 and C-6 on the cyclohexanone unit in 7 is opposite to that of 4–6. Compound 3 was revealed to have a tert-butyl-containing polyketide, β-alanine, and a PKS/NRPS-derived γ-isopropyl pyrrolinone. Compound 2 may be a hydrolysis product of 3. Of the seven new compounds, 1 showed the most potent cytotoxicity to human H-460 lung cancer cells.

N-acylpyridinium trifluoromethanesulfonates and tetrafluoroborates: Shuttle reagents for the acylation of enantiopure secondary alcohols

Several enanflopure alcohols are esterified with N-acyl-4- benzylpyfidinium trifluoromethanesulfonates 7b,d,f or tetrafluoroborates 7a,c,e. These reagents, which can be generated in situ, or isolated as stable salts, are synthesized from readily available 4-alkylpyridines 3, acyl chlorides 4 and strong protic acids 6. The acyl moiety is transferred under neutral conditions and in high yields. The heterocyclic component 3a can be re-isolated almost quantitatively. The acetate, benzoate and pivaloate groups were selected with regard to their application as frequently used protecting groups for hydroxy compounds. As shown by paramagnetic shift experiments with a chiral europium(III) complex, these acylations proceed without detectable racemization or epimerization.

Branched-Chain Carbohydrate Lactones from a Samarium(II) Iodide-Promoted Serial Deoxygenation-Carbonyl Addition Reaction

A new deoxygenation-carbonyl addition reaction mediated by samarium(II) iodide (SmI2) in THF/HMPA was examined with carbohydrate lactones and several substrates containing an α-alkoxy carboxylic ester.In a single reaction, these compounds were deoxygenate

On the Acylation of Hydroxy- and Mercaptocarboxylic Acid Esters Using the Carbodiimide/Acylation Catalyst Method

Acylation of esters of hydroxycarboxylic acids can be carried out easily and in good yields by using the carbodiimide/acylation catalyst method.The reaction has also been applied to dihydroxy- and mercaptocarboxylic acid esters.The compounds formed from certain esters of hydroxycarboxylic acids are unstable to heat and decompose easily to free carboxylic acids.Use of racemic carboxylic acids leads to diastereomers, whose (1)H-NMR shifts for characteristic protons are different as expected.Five drugs are among the carboxylic acids investigated in this context.

Substitution of 2-(Sulfonyloxy)carboxylates with Oxygene and Sulfur Nucleophiles without Racemization

The ethyl 2-(sulfonyloxy)propionates (S)-1a-c react with phenolates formed from 2 and with carboxylates 8 to give the respective 2-(aryloxy)- (R)-3 and 2-(acyloxy)propionates (R)-9 with inversion of configuration.Due to the high leaving tendency of the triflate group, (S)-1a generally give higher yields of substitution products under milder conditions than the corresponding mesylate (S)-1b and tosylate (S)-1c.In the case of the reaction of malic and succinic acid derivatives only the triflate (S)-10a is converted to the acyloxy compounds (R)-12 with carboxylates 8 atlow temperature (-45 deg C); with the mesylates 10b and the bromide 10d only elimination is observed.Mercaptides and thiophenolates formed from 17 react with (S)-1a-c analogously.With potassium thiocyanate 1a,b react almost exclusively to give the thiocyanate 19; only traces of the corresponding isothiocyanate 20 are obtained.