Corey Lactone Research Articles

A study on inhibition efficiency of (-)-corey lactone diol as corrosion inhibitor for low carbon steel, in hydrochloric acid: Surface characterisation and quantum studies

A study on inhibition efficiency of (-)-corey lactone diol as corrosion inhibitor for low carbon steel, in hydrochloric acid: Surface characterisation and quantum studies

A concise and scalable chemoenzymatic synthesis of prostaglandins

Prostaglandins have garnered significant attention from synthetic chemists due to their exceptional biological activities. In this report, we present a concise chemoenzymatic synthesis method for several representative prostaglandins, achieved in 5 to 7 steps. Notably, the common intermediate bromohydrin, a radical equivalent of Corey lactone, is chemoenzymatically synthesized in only two steps, which allows us to complete the synthesis of prostaglandin F2α in five steps on a 10-gram scale. The chiral cyclopentane core is introduced with high enantioselectivity, while the lipid chains are sequentially incorporated through a cost-effective process involving bromohydrin formation, nickel-catalyzed cross-couplings, and Wittig reactions. This cost-efficient synthesis route for prostaglandins holds the potential to make prostaglandin-related drugs more affordable and facilitate easier access to their analogues.

A facile synthesis of (±)-15-deoxy-Δ12,14-prostaglandin J2 methyl ester

A simple and facile synthesis of racemic 15-deoxy-Δ12,14-prostaglandin J2 methyl ester from readily available Corey lactone diol in total eleven steps was suggested. The standard methods provided a pathway to a block with an integrated w w w-chain and further to PGJ2 methyl ester. The latter was smoothly converted to the target prostaglandin in the TsOH–CH2Cl2 medium when allylic alcohol moiety was transformed to exocyclic diene substituent conjugated with endocyclic enone system.

Catalytic Enantioselective Inverse-Electron-Demand Diels–Alder Reaction of 2-Pyrones and Vinyl Selenides

AbstractWe report an asymmetric inverse-electron-demand Diels–Alder reaction of electron-deficient 2-pyrones with various phenyl vinyl selenides catalyzed by a chiral bis(oxazoline)/Cu(OTf)2 complex. By using a side-arm-modified chiral bis(oxazoline)ligand, a variety of [2,2,2]-bicyclic lactones with phenyl selenide substituents were obtained in good to excellent yields (up to 99%) and enantioselectivities (up to 98% ee) under mild conditions. Based on this strategy, a highly concise enantioselective synthesis of the Corey lactone was accomplished.

A Novel Synthesis of 5E-Isomer-Free Carboprost Methyl Ester

AbstractA macrocyclic lactone strategy for the synthesis of 5E-isomer-free carboprost methyl ester was developed for the first time. The macrocyclic lactone being free of 5E-isomer can be easily prepared from modified Corey lactone. The key intermediate could be used as a building scaffold to prepare carboprost methyl ester and other prostaglandins effectively.

Time and Pot Economy in Total Synthesis.

We would all like to make or obtain the materials or products we want as soon as possible. This is human nature. This is true also for chemists in the synthesis of organic molecules. All chemists would like to make their target molecules as soon as possible, particularly when their interest is in the physical or biological properties of those molecules.As demonstrated by today's COVID-19 (SARS-CoV-2) pandemic, rapid synthesis is also crucial to enable chemists to deliver effective therapeutic agents to the community. Several concepts are currently well-accepted as important for achieving this: atom economy, step economy, and redox economy. Considering the importance of synthesizing organic molecules rapidly, I recently proposed adding the concept of time economy.In a multisep synthesis, each step has to be completed within a short period of time to make the desired molecule rapidly. The development of rapid reactions is important but also insufficient. After each step, frequent and repetitive workup operations such as quenching the reaction, extraction, separation of water and organic phases, drying the organic phase, filtration, evaporation, and purification may be required, and the time necessary for these processing operations must be taken into account. Indeed, some of the most time-consuming operations in most syntheses are the purification stages.On the other hand, one-pot reactions are processes in which several sequential reactions are conducted in a single reaction vessel, which avoids the need to purify intermediates. One-pot reactions are a useful way to shorten the total synthesis time, and the approach generally leads to an increase in the yield and a reduction in the amount of chemical waste formed. Thus, I also propose the importance of pot economy.On the basis of these concepts of time and pot economy, we have accomplished efficient syntheses of several natural products and medicines. The key to the success of these syntheses is the use of diphenylprolinol silyl ether as an effective catalyst in a one-pot reaction, in which it does not disturb the subsequent reactions. Our strategy is (1) to construct the chiral key skeletons and/or key components of natural products and medicines directly using organocatalyst-mediated one-pot reactions and (2) to conduct the subsequent transformations to the final molecules in a small number of pots utilizing the internal quench method. By means of this strategy, PGE1 methyl ester, estradiol methyl ether, and clinprost were synthesized in three, five, and seven pots, respectively. Furthermore, (-)-oseltamivir, ABT-341, baclofen, and Corey lactone were synthesized in a single reaction vessel. Further optimization of the reactions in terms of time economy allowed (-)-oseltamivir and Corey lactone to be synthesized within 60 and 152 min, respectively. These syntheses will be highlighted as case studies. Although the organocatalyst is a key compound in this Account, pot- and time-economical syntheses can be expanded to organometallic chemistry and, indeed, to organic chemistry in general.

Synthesis of the Corey Lactone and Latanoprost

Key words latanoprost - Corey lactone - prostaglandins - organocatalysis - asymmetric domino Michael–Michael reaction - Fleming–Tamao oxidation

An alternative synthesis for iloprost via a key bicyclic aldehyde intermediate

An alternative synthesis for iloprost has been accomplished in 14 steps via a convergent synthesis starting from commercially available (−)-Corey lactone diol. The syntheses employ a new and key chiral bicyclic aldehyde (4) intermediate, which is primed for attachment of the required α-side chain and ω-side chain.

Time Economy in Total Synthesis

It is often said that "time is money". This is certainly true in a multistep synthesis when a high-valued product or set of products is needed urgently. Fulfilling this need requires the sensible balancing of atom economy, step economy, and redox economy with the time taken to make the product. In this age of flu-based pandemics, the need for rapid provision of effective therapeutic agents makes the importance of "time economy" particularly clear. In this Perspective, the importance of time economy in total synthesis is described, as well as the general considerations underlining the timely production of desired molecules. As case studies, the syntheses of Tamiflu, Corey lactone, and ibuprofen are discussed, with emphasis on comparing classical and contemporary approaches to a rapid total synthesis. By using modern tactics such as one-pot reaction procedures and versatile synthetic methodologies such as organocatalyst mediated domino reactions coupled with strict-control technologies such as flow chemistry, Tamiflu and Corey lactone can now be synthesized within 60 and 152 min, respectively, using one vessel via a batch system. Tamiflu and ibuprofen can be prepared via flow system, and their total residence times are 11.5 and 3 min, respectively.

Asymmetric Synthesis of Corey Lactone and Latanoprost

Corey lactone was synthesized in a single pot within 152 minutes in a 50 % overall yield via pot and time economical manner. Latanoprost, an antiglaucoma blockbuster drug, was also synthesized via seven pot reaction with five purifications in a 25 % total yield. One of the key reactions is asymmetric domino Michael/Michael reaction, formal [3+2] cycloaddition reaction, of 3‐(dimethylphenylsilyl)propenal and ethyl 4‐oxo‐2‐pentenoate, catalyzed by diphenylprolinol silyl ether, which constructed the core substituted cyclopentanone derivative with nearly optically pure form.

Pot-Economic Organocatalytic Asymmetric Synthesis of the Corey Lactone

Pot-Economic Organocatalytic Asymmetric Synthesis of the Corey Lactone

Methyl (S)-(5-methylidene-4-oxocyclopent-2-en-1-yl)acetate as a readily available pharmacologically important subunit of cross-conjugated cyclopentenone prostaglandins

A short and convenient synthesis of exomethylidenecyclopentenone core of cyclopentenone prostaglandins (+)−3 from (−) Corey lactone diol is described. The chiral 5-phenylthio and 5-phenylsulfonyl derivatives of exomethylidenecyclopentenone were obtained and their cytotoxic properties were studied in comparison with the synthesized earlier ethylthio and ethylsulfonyl derivatives of (±)−3, announced as its more stable bioisosteres.

Pot and time economies in the total synthesis of Corey lactone.

The Corey lactone is a highly versatile intermediate for the synthesis of a variety of prostaglandin hormones that natively control a multitude of important physiological processes. Starting from commercially available compounds, we herein disclose a time-economical, one-pot enantioselective preparation of the Corey lactone by virtue of a new diphenylprolinol silyl ether-mediated domino Michael/Michael reaction to afford the substituted cyclopentanone core in a formal (3 + 2) cycloadditive fashion. More broadly, this work advances the on-demand, gram-scale synthesis of high-value targets involving chemically orthogonal transformations, whereby distinct reactions of acids, bases, organometalics, reductants and oxidants can be carried out in a single reaction vessel in a sequential fashion.

HPLC and SFC enantioseparation of (±)-Corey lactone diol: Impact of the amylose tris-(3,5-dimethylphenylcarbamate) coating amount on chiral preparation.

As an important intermediate of prostaglandins and entecavir, optically pure Corey lactone diol (CLD) has great value in the pharmaceutical industry. In this work, the enantioseparation of (±)-CLD was evaluated using high-performance liquid (HPLC) and supercritical fluid chromatography (SFC). In HPLC, the separations of CLD enantiomers on polysaccharide-based chiral stationary phases with both normal phase and polar organic phase were screened. And the conditions for the enantioseparation were optimized in HPLC and SFC, including the selection of mobile phase, temperature, back-pressure, and other conditions. More important, it was found that the chiral resolutions were greatly enhanced by the increase of the coating amount of ADMPC (amylose tris-(3,5-dimethylphenylcarbamate)) under both HPLC and SFC conditions, which can lead to the increase of the productivity and the decrease of the solvent consumption. The preparations of optically pure CLD were evaluated on a semi-preparative (2×25cm) column packed with 30% ADMPC-coated CSP under HPLC and SFC conditions. Preparative performances in terms of kkd are 1.536kg racemate/kg CSP/day and 1.248kg racemate/kg CSP/day in HPLC and SFC, respectively.

Proteasome inhibitors modulate anticancer and anti-proliferative properties via NF-kB signaling, and ubiquitin-proteasome pathways in cancer cell lines of different organs

BackgroundCancer is second most common cause of death in the United State. There are over 100 different types of cancer associated with different human organs, predominantly breast, liver, pancreas, prostate, colon, rectum, lung, and stomach. We have recently reported properties of pro-inflammatory (for treatment of various types of cancers), and anti-inflammatory (for cardiovascular disease and diabetes) compounds. The major problem associated with development of anticancer drugs is their lack of solubility in aqueous solutions and severe side effects in cancer patients. Therefore, the present study was carried out to check anticancer properties of selected compounds, mostly aqueous soluble, in cancer cell lines from different organs.MethodsThe anticancer properties, anti-proliferative, and pro-apoptotic activity of novel naturally occurring or FDA approved, nontoxic, proteasome inhibitors/activators were compared. In addition to that, effect of δ-tocotrienol on expression of proteasome subunits (X, Y, Z, LMP7, LMP2, LMP10), ICAM-1, VCAM-1, and TNF-α using total RNAs derived from plasmas of hepatitis C patients was investigated.ResultsOur data demonstrated that following compounds are very effective in inducing apoptosis of cancer cells: Thiostrepton, dexamethasone, 2-methoxyestradiol, δ-tocotrienol, quercetin, amiloride, and quinine sulfate have significant anti-proliferation properties in Hela cells (44% - 87%) with doses of 2.5–20 μM, compared to respective controls. Anti-proliferation properties of thiostrepton, 2-methoxyestradiol, δ-tocotrienol, and quercetin were 70% - 92%. However, thiostrepton, dexamethasone, 2-methoxyestradiol, δ-tocotrienol, quercetin, and quinine sulphate were effective in pancreatic, prostate, breast, lungs, melanoma, Β-lymphocytes, and T-cells (Jurkat: 40% to 95%) compared to respective controls. In lung cancer cells, these compounds were effective between 5 and 40 μM. The IC50 values of anti-proliferation properties of thiostrepton in most of these cell lines were between doses of 2.5–5 μM, dexamethasone 2.5–20 μM, 2-methoxyestradiol 2.5–10 μM, δ-tocotrienol 2.5–20 μM, quercetin 10–40 μM, and (−) Corey lactone 40–80 μM. In hepatitis C patients, δ-tocotrienol treatment resulted in significant decrease in the expression of pro-inflammatory cytokines.ConclusionsThese data demonstrate effectiveness of several natural-occurring compounds with anti-proliferative properties against cancer cells of several organs of humans. Thiostrepton, dexamethasone, 2-methoxyestradiol, δ-tocotrienol and quercetin are very effective for apoptosis of cancer cells in liver, pancreas, prostate, breast, lung, melanoma, Β-lymphocytes and T-cells. The results have provided an opportunity to test these compounds either individually or in combination as dietary supplements in humans for treatment of various types of cancers.

Synthesis of racemic Entecavir

Racemic Entecavir was prepared from Corey lactone diol benzylidene acetal in four steps in 24% overall yield.

A short synthesis of the carbocyclic core of Entecavir from Corey lactone

The readily available Corey lactone was converted in three simple stages to tris-TBS-ether of (1 R *,3 R *,5 S *)-1-hydroxymethyl-3,5-dihydroxy-2-methylidenecyclopentane – the protected carbocyclic core of Entecavir, one of the best medicines against hepatitis.

A Facile and Efficient Synthesis of (15R)-Latanoprost from Chiral Precursor Corey Lactone Diol

An efficient asymmetric synthetic route for the synthesis of anti-glaucoma agent, (15R)-latanoprost using Corey lactone diol as chiral substrate under Swern oxidation, allylic reduction and Wittig reaction conditions has been developed. In this method, reduction of keto and alkene functional groups has been achieved in a single step using low cost catalyst NiCl2/NaBH4 in methanol. This new synthetic protocol is a good alternative for the synthesis of latanoprost with high stereo selectivity and improved yield. A simple, convenient and convergent approach for the synthesis of (15R) latanoprost is reported with high stereo selectivity and improved yield from chiral precursor Corey lactone diol using Swern oxidation, allylic reduction and Wittig reaction conditions.

An Improved and Efficient Process for the Preparation of (+)-cloprostenol.

An improved and efficient synthesis of (+)-cloprostenol has been accomplished in nine steps and 26% overall yield from commercially available (-)-Corey lactone 4-phenylbenzoate alcohol . The present route avoids tedious purifications and requires only one column chromatography operation, which reduces the generation of waste and is suitable for large-scale preparation.

前列腺素类药物关键中间体Corey Lactone的合成工艺研究

目前市场上已开发出的前列腺素类似物药物,主要是以Corey lactone关键中间体法进行人工合成。本文以降冰片二烯为原料，经Prins反应，Baeyer-Villiger氧化等一系列反应，成功制成了Corey lactone，并经LC-MS, NMR结构确认；在反应过程中对关键手性中间体进行拆分工艺的研究，最终确认路线中所用到的拆分试剂以及溶剂较其他报道常见且价格低廉，易于工业化生产。 Corey lactone is the key intermediate of synthetizing the prostaglandin analogues. In this paper, we use the norbornadiene as the raw material to synthetize the Corey lactone. Through Prins reaction, Baeyer-Villiger oxidation, splitting the chiral intermediate and a series of reaction successfully, the structure has been confirmed by the LC-MS and the NMR. The reagent and the solvent which are used in this method are so common and inexpensive that they can be suitable for industrialized production.