137688-21-2Relevant academic research and scientific papers
Total synthesis and anti-inflammatory bioactivity of (?)-majusculoic acid and its derivatives
Xiao, Hong-Xiu,Yan, Qing-Xiang,He, Zhi-Hui,Zou, Zheng-Biao,Le, Qing-Qing,Chen, Ting-Ting,Cai, Bing,Yang, Xian-Wen,Luo, Su-Lan
, (2021)
The first total synthesis of marine natural product, (?)-majusculoic acid (1) and its seven analogs (9–15), was accomplished in three to ten steps with a yield of 3% to 28%. The strategy featured the application of the conformational controlled establishment of the trans-cyclopropane and stereochemical controlled bromo-olefination or olefination by Horner–Wadsworth–Emmons (HWE) reaction. The potential anti-inflammatory activity of the eight compounds (1 and 9–15) was evaluated by determining the nitric oxide (NO) production in the lipopolysaccharide (LPS)-induced mouse macrophages RAW264.7. (?)-Majusculoic acid (1), methyl majusculoate (9), and (1R,2R)-2-((3E,5Z)-6-bromonona-3,5-dien-1-yl)cyclopropane-1-carboxylic acid (12) showed significant effect with inhibition rates of 33.68%, 35.75%, and 43.01%, respectively. Moreover, they did not show cytotoxicity against RAW264.7 cells, indicating that they might be potential anti-inflammatory agents.
Discovery of piperidine ethers as selective orexin receptor antagonists (SORAs) inspired by filorexant
Raheem, Izzat T.,Breslin, Michael J.,Bruno, Joseph,Cabalu, Tamara D.,Cooke, Andrew,Cox, Christopher D.,Cui, Donghui,Garson, Susan,Gotter, Anthony L.,Fox, Steven V.,Harrell, C. Meacham,Kuduk, Scott D.,Lemaire, Wei,Prueksaritanont, Thomayant,Renger, John J.,Stump, Craig,Tannenbaum, Pamela L.,Williams, Peter D.,Winrow, Christopher J.,Coleman, Paul J.
, p. 444 - 450 (2015/01/30)
Highly selective orexin receptor antagonists (SORAs) of the orexin 2 receptor (OX2R) have become attractive targets both as potential therapeutics for insomnia as well as biological tools to help further elucidate the underlying pharmacology of the orexin signaling pathway. Herein, we describe the discovery of a novel piperidine ether 2-SORA class identified by systematic lead optimization beginning with filorexant, a dual orexin receptor antagonist (DORA) that recently completed Phase 2 clinical trials. Changes to the ether linkage and pendant heterocycle of filorexant were found to impart significant selectivity for OX2R, culminating in lead compound PE-6. PE-6 displays sub-nanomolar binding affinity and functional potency on OX2R while maintaining >1600-fold binding selectivity and >200-fold functional selectivity versus the orexin 1 receptor (OX1R). PE-6 bears a clean off-target profile, a good overall preclinical pharmacokinetic (PK) profile, and reduces wakefulness with increased NREM and REM sleep when evaluated in vivo in a rat sleep study. Importantly, subtle structural changes to the piperidine ether class impart dramatic changes in receptor selectivity. To this end, our laboratories have identified multiple piperidine ether 2-SORAs, 1-SORAs, and DORAs, providing access to a number of important biological tool compounds from a single structural class.
Bioproduction of chiral epoxyalkanes using styrene monooxygenase from rhodococcus sp. ST-10 (RhSMO)
Toda, Hiroshi,Imae, Ryouta,Itoh, Nobuya
, p. 3443 - 3450 (2015/02/05)
We describe the enantioselective epoxidation of straight-chain aliphatic alkenes using a biocatalytic system containing styrene monooxygenase from Rhodococcus sp. ST-10 and alcohol dehydrogenase from Leifsonia sp. S749. The biocatalyzed enantiomeric epoxidation of 1-hexene to (S)-1,2-epoxyhexane (44.6 mM) using 2-propanol as the hydrogen donor was achieved under optimized conditions. The biocatalyst had broad substrate specificity for various aliphatic alkenes, including terminal, internal, unfunctionalized, and di- and tri-substituted alkenes. Here, we demonstrate that this biocatalytic system is suitable for the efficient production of enantioenriched (S)-epoxyalkanes.
Asymmetric hydrolytic kinetic resolution with recyclable polymeric Co(iii)-salen complexes: A practical strategy in the preparation of (S)-metoprolol, (S)-toliprolol and (S)-alprenolol: Computational rationale for enantioselectivity
Roy, Tamal,Barik, Sunirmal,Kumar, Manish,Kureshy, Rukhsana I.,Ganguly, Bishwajit,Khan, Noor-Ul H.,Abdi, Sayed H. R.,Bajaj, Hari C.
, p. 3899 - 3908 (2015/02/19)
A series of chiral polymeric Co(iii)-salen complexes based on a number of achiral and chiral linkers were synthesized and their catalytic performances were assessed in the asymmetric hydrolytic kinetic resolution of terminal epoxides. The effects of the linker were judiciously studied and it was found that in the case of the chiral BINOL-based polymeric salen complex 1, there was an enrichment in catalyst reactivity and enantioselectivity of the unreacted epoxide, particularly in the case of short as well as long chain aliphatic epoxides. Good isolated yields of the unreacted epoxide (up to 46% compared to 50% theoretical yield) along with high enantioselectivity (up to 99%) were obtained in most cases using catalyst 1. Further studies showed that catalyst 1 could retain its catalytic activity for six cycles under the present reaction conditions without any significant loss in activity or enantioselectivity. To show the practical applicability of the above synthesized catalyst we have synthesised some potent chiral β-blockers in moderate yield and high enantioselectivity using complex 1. The DFT (M06-L/6-31+G??//ONIOM(B3LYP/6-31G?:STO-3G)) calculations revealed that the chiral BINOL linker influences the enantioselectivity achieved with Co(iii)-salen complexes. Further, the transition state calculations show that the R-BINOL linker with the (S,S)-Co(iii)-salen complex is energetically preferred over the corresponding S-BINOL linker with the (S,S)-Co(iii)-salen complex for the HKR of 1,2-epoxyhexane. The role of non-covalent C-H?π interactions and steric effects has been discussed to control the HKR reaction of 1,2-epoxyhexane.
Minimal fluorous tagging strategy that enables the synthesis of the complete stereoisomer library of SCH725674 macrolactones
Moretti, Jared D.,Wang, Xiao,Curran, Dennis P.
supporting information; experimental part, p. 7963 - 7970 (2012/06/30)
Four mixtures of four fluorous-tagged quasiisomers have been synthesized, demixed, and detagged to make all 16 stereoisomers of the macrocyclic lactone natural product Sch725674. A new bare-minimum tagging pattern needs only two tags-one fluorous and one nonfluorous-to encode four isomers. The structure of Sch725674 is assigned as (5R,6S,8R,14R,E)-5,6,8-trihydroxy-14- pentyloxacyclotetradec-3-en-2-one. Various comparisons of spectra of 32 lactones (16 with tags, 16 without) and 16 ester precursors (8 with tags, 8 without) provide insights into when and why related compounds have the same or different spectra.
ISOSELECTIVE POLYMERIZATION OF EPOXIDES
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Page/Page column 69; 75-76, (2009/04/25)
The present invention provides novel bimetallic complexes and methods of using the same in the isoselective polymerization of epoxides. The invention also provides methods of kinetic resolution of epoxides. The invention further provides polyethers with high enantiomeric excess that are useful in applications ranging from consumer goods to materials.
Efficient and flexible synthesis of chiral γ- And δ-lactones
Habel, Andreas,Boland, Wilhelm
supporting information; experimental part, p. 1601 - 1604 (2008/10/09)
An efficient and highly flexible synthesis for chiral γ- and δ-lactones with high enantiomeric purity is described (>99% ee and 57-87% overall yield). The protocol involves alkylation of chiral 1,2-oxiranes with terminally unsaturated Grignard reagents. Subsequent oxidative degradation (OsO4-Oxone) of the terminal double bond from chiral alk-1-en-5-ols and alk-1-en-6-ols affords 4- or 5-hydroxy acids and γ- and δ-lactones after acidic workup. The flexibility and efficiency of the protocol is illustrated by the synthesis of several alkanolides and alkenolides, hydroxy fatty acids and dihydroisocoumarins. The Royal Society of Chemistry 2008.
NEW CHIRAL SALEN CATALYSTS AND METHODS FOR THE PREPARATION OF CHIRAL COMPOUNDS FROM RACEMIC EPOXIDES BY USING THEM
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Page/Page column 39, (2009/01/24)
The present invention relates to new chiral salen catalysts and the preparation method of chiral compounds from racemic epoxides using the same. More specifically, it relates to new chiral salen catalysts that have high catalytic activity due to new molecular structures and have no or little racemization of the generated target chiral compounds even after the reaction is completed and can be also reused without catalyst regeneration treatment, and its economical preparation method to mass manufacture chiral compounds of high optical purity, which can be used as raw materials for chiral food additives, chiral drugs, or chiral crop protection agents, etc., using the new chiral salen catalysts.
Aldolase antibody activation of prodrugs of potent aldehyde-containing cytotoxics for selective chemotherapy
Sinha, Subhash C.,Li, Lian-Sheng,Watanabe, Shin-Ichi,Kaltgrad, Eiton,Tanaka, Fujie,Rader, Christoph,Lerner, Richard A.,Barbas III, Carlos F.
, p. 5467 - 5472 (2007/10/03)
Prodrugs of potent aldehyde analogues of the anticancer drug doxorubicin (Dox) were synthesized. These prodrugs were efficiently activated by antibody 93F3 and no drug formation was observed in the absence of 93F3 in either phosphate buffered saline or cell culture media. In the presence of antibody 93F3, these prodrugs were activated and decreased the proliferation of human cancer cells in in vitro proliferation assays.
Highly selective hydrolytic kinetic resolution of terminal epoxides catalyzed by chiral (salen)CoIII complexes. Practical synthesis of enantioenriched terminal epoxides and 1,2-diols
Schaus, Scott E.,Brandes, Bridget D.,Larrow, Jay F.,Tokunaga, Makoto,Hansen, Karl B.,Gould, Alexandra E.,Furrow, Michael E.,Jacobsen, Eric N.
, p. 1307 - 1315 (2007/10/03)
The hydrolytic kinetic resolution (HKR) of terminal epoxides catalyzed by chiral (salen)CoIII complex 1·OAc affords both recovered unreacted epoxide and 1,2-diol product in highly enantioenriched form. As such, the HKR provides general access to useful, highly enantioenriched chiral building blocks that are otherwise difficult to access, from inexpensive racemic materials. The reaction has several appealing features from a practical standpoint, including the use of H2O as a reactant and low loadings (0.2-2.0 mol %) of a recyclable, commercially available catalyst. In addition, the HKR displays extraordinary scope, as a wide assortment of sterically and electronically varied epoxides can be resolved to ≥ 99% ee. The corresponding 1,2-diols were produced in good-to-high enantiomeric excess using 0.45 equiv of H2O. Useful and general protocols are provided for the isolation of highly enantioenriched epoxides and diols, as well as for catalyst recovery and recycling. Selectivity factors (krel) were determined for the HKR reactions by measuring the product ee at ca. 20% conversion. In nearly all cases, krel values for the HKR exceed 50, and in several cases are well in excess of 200.
