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1.
Org Biomol Chem ; 22(3): 550-553, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38112044

RESUMEN

We synthesized fulgidic acid and the proposed structure for chaenomic acid D. The core part of the two natural products was constructed stereoselectively by the addition of acetic acid to the α,ß-unsaturated epoxy alcohol in the presence of a palladium catalyst. Subsequently, the two natural products were synthesized from the intermediate in a few steps. The data for the synthesized fulgidic acid were in good agreement with the reported data. Chaenomic acid was in good agreement with the natural product in the 1H and 13C NMR data, but not in the optical rotation. The 15R-isomer of chaenomic acid was also synthesized, but the 1H and 13C NMR data did not agree with the natural product.

2.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38474038

RESUMEN

Biofilm-associated bacterial infections are the major reason for treatment failure in many diseases including burn trauma infections. Uncontrolled inflammation induced by bacteria leads to materiality, tissue damage, and chronic diseases. Specialized proresolving mediators (SPMs), including maresin-like lipid mediators (MarLs), are enzymatically biosynthesized from omega-3 essential long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA), by macrophages and other leukocytes. SPMs exhibit strong inflammation-resolving activities, especially inflammation provoked by bacterial infection. In this study, we explored the potential direct inhibitory activities of three MarLs on Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria in their biofilms that are leading bacteria in burn trauma-related infections. We also examined the effects of MarLs on the bactericidal activities of a typical broad-spectrum antibiotic, carbenicillin (carb), on these bacteria in their preformed biofilms. The results revealed that MarLs combined with carbenicillin can inhibit the survival of Gram-positive and Gram-negative bacteria in their biofilms although MarLs alone did not exhibit bactericidal activity. Thus, our findings suggest that the combination of MarLs and carbenicillin can lower the antibiotic requirements to kill the bacteria in preformed biofilms.


Asunto(s)
Quemaduras , Enfermedades Transmisibles , Infecciones Estafilocócicas , Infección de Heridas , Humanos , Antibacterianos/farmacología , Carbenicilina/farmacología , Bacterias Gramnegativas , Bacterias Grampositivas , Biopelículas , Bacterias , Escherichia coli , Inflamación , Pruebas de Sensibilidad Microbiana
3.
Biochem Biophys Res Commun ; 599: 127-133, 2022 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-35180472

RESUMEN

Acute lung injury is one of major complications associated with sepsis, responsible for morbidity and mortality. Patients who suffer from acute lung injury often require respiratory support under sedations, and it would be important to know the role of sedatives in lung injury. We examined volatile anesthetic isoflurane, which is commonly used in surgical setting, but also used as an alternative sedative in intensive care settings in European countries and Canada. We found that isoflurane exposure attenuated neutrophil recruitment to the lungs in mice suffering from experimental polymicrobial abdominal sepsis. We found that isoflurane attenuated one of major neutrophil chemoattractants LTB4 mediated response via its receptor BLT1 in neutrophils. Furthermore, we have shown that isoflurane directly bound to BLT1 by a competition assay using newly developed labeled BLT1 antagonist, suggesting that isoflurane would be a BLT1 antagonist.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/etiología , Isoflurano/farmacología , Sepsis/complicaciones , Anestésicos por Inhalación/farmacología , Animales , Quimiotaxis/efectos de los fármacos , Modelos Animales de Enfermedad , Eicosanoides/metabolismo , Isoflurano/química , Isoflurano/metabolismo , Leucotrieno B4/metabolismo , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Ratones Endogámicos C57BL , Infiltración Neutrófila/efectos de los fármacos , Receptores de Leucotrieno B4/antagonistas & inhibidores , Receptores de Leucotrieno B4/química , Receptores de Leucotrieno B4/metabolismo , Sepsis/fisiopatología
4.
Org Biomol Chem ; 20(21): 4338-4341, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35551327

RESUMEN

Resolvin D3 was synthesized by the Suzuki-Miyaura cross-coupling reaction of C1-C8 borane with C9-C22 iodoolefin as the key reaction. The latter intermediate was obtained by the sequential Wittig reactions of C9-C13 phosphonium salt with C14-C19 aldehyde and then C9-C19 aldehyde with propyltriphenylphosphonium bromide. The stereogenic centers at C4, C11, and C17 were constructed by the ruthenium-catalyzed asymmetric transfer hydrogenation with high stereoselectivity.


Asunto(s)
Aldehídos , Ácidos Grasos Insaturados , Hidrogenación , Estereoisomerismo
5.
Chemistry ; 27(11): 3779-3785, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33128320

RESUMEN

The regioselectivity (r.s.) and enantiospecificity (e.s.) of the substitution reactions of secondary propargylic alcohol derivatives using reagents derived from ArMgBr and Cu salts were studied. First, the picolinate, 3-methylpicolinate, and diethylphosphonate derivatives of Ph(CH2 )2 CH(OH)C≡CTMS were reacted with PhMgBr/CuCN in ratios of 2.5:2.7-2.5:0.25. The use of 2.5:0.25 ratio in THF/DME (6:1) at 0 °C for 1 h afforded the α-substitution product from the phosphate with ≥98 % r.s. and 99 % e.s. CuBr⋅Me2 S gave similar selectivity. The reaction system was then applied to phosphates derived from R1 CH(OH)C≡CR2 and ArMgBr to obtain synthetically sufficient r.s. and e.s. values with R2 =TMS, Ph, whereas iPr was borderline in terms of size as an R1 substituent. The presence of a substituent at the o-position of Ar marginally affected the selectivity. We also found that the use of PhMgBr/Cu(acac)2 in a 2:1 ratio in THF produced the γ-substitution products (allenes) with high r.s. and e.s.

6.
Org Biomol Chem ; 19(45): 9906-9909, 2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34734958

RESUMEN

The copper-catalyzed substitution reaction of diethyl phosphate derived from TMSCCCH(OH)CH2CH2OTBDPS with 3-c-C5H9-4-MeOC6H3MgBr, followed by several transformations, afforded a tumor necrosis factor inhibitor possessing a Ph-acetylene moiety. The inhibitor was also synthesized from phenylacetylene phosphate PhCCCH(OP(O)(OEt)2)CH2CH2OTBDPS. Furthermore, the substitution of phosphates derived from TMSCCCH(OH)CH3 and TMSCCCH(OH)-i-Pr with 3-F-4-PhC6H3MgBr gave the corresponding substitution products, which were transformed to flurbiprofen and its i-Pr analogue, respectively. The copper-catalyzed substitutions in these syntheses proceeded in a regio- and stereoselective manner.


Asunto(s)
Alquinos/química , Cobre/química , Flurbiprofeno/síntesis química , Indicadores y Reactivos/química , Propanoles/química , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Catálisis , Flurbiprofeno/química , Flurbiprofeno/farmacología , Estereoisomerismo
7.
Org Biomol Chem ; 17(9): 2393-2402, 2019 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-30729968

RESUMEN

(18R)- and (18S)-stereoisomers of resolvin E3 (RvE3), potent anti-inflammatory mediators, were synthesized stereo- and enantioselectively through the Wittig reaction of the carbonate of 6R,7R- and 6R,7S-dihydroxynona-2E,4E-dienal, a C12-C20 part, with the phosphonium salt corresponding to the C1-C11 part. The stereoisomeric carbonate was prepared by the Swern oxidation of 3-(AcO)-6R,7R- or 3-(AcO)-6R,7S-(dihydroxy-carbonate)-4-nonen-1-ol followed by the spontaneous elimination of the AcO group in one pot. The (6R,7R)-(dihydroxy-carbonate)-alcohol for (18R)-RvE3 was, in turn, provided by stereoselective epoxidation of 9-(TBS-oxy)nona-4Z,6E-dien-3R-ol with m-CPBA and the subsequent Pd-catalyzed addition of AcOH to the resulting syn vinyl epoxy alcohol followed by carbonate formation of the vic-syn-diol and TBS desilylation. The Mitsunobu inversion of the syn vinyl epoxy alcohol gave the anti isomer, which was converted to 3-(AcO)-6R,7S-(dihydroxy-carbonate)-4-nonen-1-ol, the intermediate to (18S)-RvE3, by the same set of reactions.

8.
Org Biomol Chem ; 17(8): 2212-2222, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30720822

RESUMEN

We studied the synthesis of RvD1, a pro-resolving mediator. The intermediate containing vic-diol and enal functional groups was prepared via the oxidation of the γ,δ-epoxy alcohol followed by the epoxide ring opening in one pot. The C11-aldehyde in the resulting enal was converted to the trans iodo-olefin by reaction with TMSC(N2)Li and subsequent hydrozirconation using in situ generated Cp2Zr(H)Cl followed by iodination. The trans enynyl alcohol was synthesized by the reaction of the TMS-containing epoxy alcohol with lithium TMS-acetylide. Finally, two fragments were joined by the Sonogashira coupling, and the triple bond was reduced to afford RvD1 stereoselectively.

9.
Biochem Biophys Res Commun ; 504(3): 562-568, 2018 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-29890138

RESUMEN

Lipids are an energy source and key components of the cell membrane; however, they are also bioactive mediators of physiological and pathophysiological phenomena. Quantification of bioactive lipids is not easy because they have diverse chemical properties and are present in trace amounts. Here, we improved a multiplex method of quantifying bioactive lipids, thereby enabling measurement of 90 compounds simultaneously. We then used this system to quantify bioactive lipids produced by two subsets of dendritic cells (DCs): all-trans retinoic acid-treated DCs (RA-DCs) (a type of tolerogenic DC (tDC)) and conventional DCs (cDCs). We found that cDCs produced inflammatory lipid mediators such as leukotrienes, whereas RA-DCs produced anti-inflammatory lipid mediators such as prostaglandin I2. Consistent with this, cDCs expressed larger amounts of mRNA encoding 5-lipoxygenase and LTA4 hydrolase (both responsible for leukotriene biosynthesis) and RA-DCs produced larger amounts of mRNA encoding prostaglandin I2 synthase. Taken together, the results suggest that the method is useful for clarifying the roles of bioactive lipids during immune responses.


Asunto(s)
Cromatografía Liquida/métodos , Células Dendríticas/química , Metabolismo de los Lípidos , Lípidos/análisis , Metabolómica/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Eicosanoides/análisis , Eicosanoides/metabolismo , Humanos , Ratones Endogámicos C57BL , Tretinoina/farmacología
10.
J Org Chem ; 83(7): 3906-3914, 2018 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-29547275

RESUMEN

The stereoselective synthesis of resolvin D4 (RvD4) was achieved using the Wittig reaction of the C1-C10 dienal with the known C11-C22 phosphonium salt. The ( S, E)-enantiomer ( S)-10, corresponding to the C1-C8 part, was synthesized in 95% ee by the asymmetric transfer hydrogenation reaction of the corresponding acetylenic ketone followed by Red-Al reduction. Sharpless epoxidation of this alcohol using Ti(O- i-Pr)4/l-(+)-DIPT as a catalyst produced anti epoxy alcohol with >99% ee as the sole product in 82% yield. A subsequent functional group manipulation, including removal of the PMB group, produced the alcohol, which upon Swern oxidation afforded anti 4-hydroxy-5-TBS-oxy enal via epoxide ring opening of the resulting aldehyde. The Horner-Wadsworth-Emmons reaction was used to add the C9-C10 enal part to this aldehyde, and the resulting dienal was subjected to the Wittig reaction with C11-C22 phosphonium salt to furnish the entire structure of RvD4. Conversion of the primary alcohol to the methyl ester and deprotection of the three TBS groups with TBAF afforded 5,17-dihydroxy-γ-lactone, which was hydrolyzed to RvD4. Additionally, anti-4,5-dihydroxydodecanoic acid, a model compound of RvD4, in CD3OD was observed to be stable at room temperature for several weeks, whereas 20% of the acid in CDCl3 was converted into the γ-lactone after 24 h at rt.


Asunto(s)
Ácidos Grasos Insaturados/síntesis química , Cetonas/química , Compuestos Organofosforados/química , Ácidos Grasos Insaturados/química , Hidrogenación , Conformación Molecular , Oxidación-Reducción , Estereoisomerismo
11.
J Org Chem ; 83(1): 154-166, 2018 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-29224348

RESUMEN

Synthesis of 14S,21R- and 14S,21S-dihydroxy-DHA (diHDHA) among the four possible stereoisomers of 14,21-diHDHA was studied. Methyl (R)-lactate (>97% ee), selected as a C20-C22 fragment (DHA numbering), was converted to the C17-C22 phosphonium salt, which was subjected to a Wittig reaction with racemic C16-aldehyde of the C12-C16 part with the TMS and TBS-oxy groups at C12 and C14, yielding the C12-C22 derivative with 14R/S and 21R chirality. Kinetic resolution using Sharpless asymmetric epoxidation of the TBS-deprotected allylic alcohol with l-(+)-DIPT/Ti(O-i-Pr)4 afforded 14S-epoxy alcohol and 14R-allylic alcohol with >99% diastereomeric excess (de) for both. The CN group was introduced to the epoxy alcohol by reaction with Et2AlCN. The 14R-allylic alcohol was also converted to the nitrile via Mitsunobu inversion. Reduction of the nitrile with DIBAL afforded the key aldehyde corresponding to the C11-C22 moiety. The Wittig reaction of this aldehyde with a phosphonium salt of the remaining C1-C10 part followed by functional group manipulation gave 14S,21R-diHDHA. Similarly, ethyl (S)-lactate (>99% ee) was converted to 14S,21S-diHDHA. The chiral LC-UV-MS/MS analysis demonstrated that each of these two 14,21-diHDHAs synthesized using the presented total organic synthesis was highly stereoselective and identical to the macrophage-produced counterpart.


Asunto(s)
Ácidos Docosahexaenoicos/síntesis química , Macrófagos/química , Ácidos Docosahexaenoicos/biosíntesis , Ácidos Docosahexaenoicos/química , Humanos , Macrófagos/metabolismo , Estructura Molecular , Estereoisomerismo
12.
Org Biomol Chem ; 16(41): 7636-7647, 2018 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-30283948

RESUMEN

Ozonolysis of TMS-substituted olefins produces α-carbonyl TMS peroxides without cleavage of the C[double bond, length as m-dash]C bond. Herein, stereochemistry in the ozonolysis was studied using silyl derivatives of (E)- and (Z)-(1-TMS)alk-1-en-3-ols. The (E)-isomers afforded the anti-3-siloxy-2-(TMS-oxy)aldehydes as the major stereoisomer (anti/syn = 3-9 : 1) after reductive work-up with Ph3P. In contrast, Z-olefins selectively gave the syn isomers with syn/anti ratios of 4-19 : 1. Facial selection was speculated based on the Cieplak effect. This ozonolysis was successfully applied for the synthesis of 14R,15S- and 14S,15S-diHETEs (anti and syn isomers, respectively) in enantioenriched forms.

13.
J UOEH ; 40(1): 33-44, 2018.
Artículo en Japonés | MEDLINE | ID: mdl-29553073

RESUMEN

We collected information necessary for conducting occupational health activities in Thailand with regard to occupational safety and health management systems (OSHMS). Based on an information collection check sheet developed in our previous research, we conducted a literature research and visited four local business bases, one ISO certification body and two higher educational institutions. The legal framework concerning occupational health in Thailand consists of the Occupational Safety, Health and Environment Act of 2011 and 13 ordinances from the Ministry of Labor under that act. The original OSHMS standards for Thailand have been published, and the number of companies, especially large ones, introducing systems conforming to these standards has increased in recent years. For occupational health specialists, there are training programs for specialized occupational health physicians, professional safety officers and occupational nurses. Professional safety officers also play a central role in occupational health in the workplace. In Thailand, it is necessary to ensure compliance with related acts and regulations, and to conduct voluntary activities that satisfy workplace conditions as based on the OSHMS standards. Additionally, to improve occupational health performance, it is essential to use high-quality external services and/or occupational health professionals. Headquarters of Japanese companies have considered taking countermeasures such as recommending active use of professional safety officers, as well as issuing global standards.


Asunto(s)
Salud Laboral , Lugar de Trabajo , Humanos , Almacenamiento y Recuperación de la Información , Salud Laboral/legislación & jurisprudencia , Médicos Laborales/educación , Tailandia
14.
J Org Chem ; 82(4): 2032-2039, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28098462

RESUMEN

Resolvin D5 (RvD5) is a metabolite of docosahexanoic acid with anti-inflammatory activity that has not yet been thoroughly investigated because of its low biological availability. A synthetic route to optically active RvD5 was developed by assembling the C1-C10 aldehyde, C11-C13 phosphonium salt, and C14-C22 aldehyde building blocks. The aldehyde fragments were prepared by Sharpless asymmetric epoxidation of corresponding racemic (E)-1-TMS-1-alken-3-ols followed by reaction of the TBS ethers of the resulting epoxy alcohols with Et2AlCN and DIBAL reduction of the (E)-1-cyano-1-alken-3-ol derivatives. The C14-C22 aldehyde was connected with the C11-C13 fragment, i.e., [TBSO(CH2)3PPh3]+ Br-, by Wittig reaction. The resulting C11-C22 intermediate was converted to the phosphonium salt, which was attached to the C1-C10 aldehyde by Wittig reaction to yield the structure of RvD5.


Asunto(s)
Ácidos Docosahexaenoicos/síntesis química , Ácidos Docosahexaenoicos/química , Estructura Molecular
15.
Org Biomol Chem ; 15(40): 8614-8626, 2017 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-28980682

RESUMEN

The reaction of TMS-substituted epoxy alcohols (and derivatives) with dimsyl sodium (NaDMSO) to give 1-alkene-3,4-diols was used for the synthesis of enantiomerically enriched 17(R),18(S)-EpETE and two diastereoisomers of isoleukotoxin diol. In the synthesis of 17(R),18(S)-EpETE, the α-ethoxyethyl ether (EE) of the epoxy alcohol derived from (R)-1-TMS-1-penten-3-ol underwent reaction with NaDMSO to give the mono EE-protected 1-hexene-3,4-diol. The aldehyde obtained by hydroboration/oxidation was subjected to Wittig reaction to afford a mono EE-protected diol. The corresponding mono mesylate was prepared and subjected to epoxide ring formation to afford 17(R),18(S)-EpETE stereoselectively. Similarly, a reaction of the anti epoxy alcohol derived from (R)-1-TMS-1-octen-3-ol with NaDMSO gave the anti form of 1-nonene-3,4-diol, which was converted to 12(S),13(R)-isoleukotoxin diol through Wittig reaction. 12(R),13(R)-Isoleukotoxin diol was synthesized in a similar manner.


Asunto(s)
Alquenos/química , Ácido Eicosapentaenoico/química , Compuestos Epoxi/síntesis química , Ácidos Oléicos/síntesis química , Estilbenos/química , Compuestos Epoxi/química , Estructura Molecular , Ácidos Oléicos/química , Estereoisomerismo
16.
Org Biomol Chem ; 14(45): 10667-10673, 2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27786324

RESUMEN

Natural 12-hydroxyheptadecatrienoic acid (12-HHT) with an S configuration was synthesised by a Suzuki-Miyaura coupling of C10-C17 iodo alcohol with C1-C9 vinylborane. The iodo alcohol was synthesised by utilising Sharpless asymmetric epoxidation of the corresponding trimethylsilyl alcohol. The method yielded more than 100 mg of 12-HHT. Similarly, syntheses of 5,6-dihydro- and 14,15-dehydro derivatives of 12-HHT, known as HHD and HHTE, respectively, were completed in a stereoselective manner.


Asunto(s)
Ácidos Grasos Insaturados/síntesis química , Alcoholes/síntesis química , Alcoholes/química , Boranos/síntesis química , Boranos/química , Compuestos Epoxi/síntesis química , Compuestos Epoxi/química , Ácidos Grasos Insaturados/química , Estereoisomerismo , Compuestos de Vinilo/síntesis química , Compuestos de Vinilo/química
17.
Nature ; 468(7322): 400-5, 2010 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-20927106

RESUMEN

Jasmonates are a family of plant hormones that regulate plant growth, development and responses to stress. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of transcriptional repressor JAZ proteins. Despite its importance, the mechanism of jasmonate perception remains unclear. Here we present structural and pharmacological data to show that the true Arabidopsis jasmonate receptor is a complex of both COI1 and JAZ. COI1 contains an open pocket that recognizes the bioactive hormone (3R,7S)-jasmonoyl-l-isoleucine (JA-Ile) with high specificity. High-affinity hormone binding requires a bipartite JAZ degron sequence consisting of a conserved α-helix for COI1 docking and a loop region to trap the hormone in its binding pocket. In addition, we identify a third critical component of the jasmonate co-receptor complex, inositol pentakisphosphate, which interacts with both COI1 and JAZ adjacent to the ligand. Our results unravel the mechanism of jasmonate perception and highlight the ability of F-box proteins to evolve as multi-component signalling hubs.


Asunto(s)
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Fosfatos de Inositol/metabolismo , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Represoras/química , Proteínas Represoras/metabolismo , Secuencia de Aminoácidos , Aminoácidos/química , Aminoácidos/metabolismo , Arabidopsis/química , Arabidopsis/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Ciclopentanos/química , Proteínas F-Box/química , Proteínas F-Box/metabolismo , Indenos/química , Indenos/metabolismo , Isoleucina/análogos & derivados , Isoleucina/química , Isoleucina/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Oxilipinas/química , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Reguladores del Crecimiento de las Plantas/química , Unión Proteica , Estructura Terciaria de Proteína , Transducción de Señal
18.
J Org Chem ; 80(18): 9192-9, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26325002

RESUMEN

The addition of MeLi to boron enolates produced by the 1,4-addition of Ar2Cu(CN)Li2 to BF3·OEt2-activated enones was followed by the reaction with ClP(O)(OEt)2 to afford the corresponding enol phosphates in moderate to good yields. The scope of this method was examined with sterically hindered or electronically biased enones and/or reagents. This activation of boron enolates was successfully applied to the synthesis of the methyl ether of Δ(9)-tetrahydrocannabinol.


Asunto(s)
Boro/química , Dronabinol/síntesis química , Indicadores y Reactivos/química , Litio/química , Éteres Metílicos/síntesis química , Compuestos Organofosforados/química , Fosfatos/química , Dronabinol/química , Éteres Metílicos/química
19.
Chemistry ; 20(1): 272-8, 2014 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-24273103

RESUMEN

Cyclohexanone with the pMeOC6H4 and CH2=C(Me) substituents at the C3 and C4-positions was prepared from (+)-ß-pinene and converted to the allylic picolinate by a Masamune-Wittig reaction followed by reduction and esterification. Allylic substitution of this picolinate with Me2CuMgBr·MgBr2 in the presence of ZnI2 proceeded with γ regio- and stereoselectively to afford the quaternary carbon center on the cyclohexane ring with the CH2=CH and Me groups in axial and equatorial positions, respectively. This product was converted to cyclobakuchiol A by demethylation and to cyclobakuchiol C by epoxidation of the CH2=C(Me) group. For the synthesis of cyclobakuchiol B, the enantiomer of the above cyclohexanone derived from (-)-ß-pinene was converted to the cyclohexane-carboxylate, and the derived enolate was subjected to the reaction with CH2=CHSOPh followed by sulfoxide elimination to afford the intermediate with the quaternary carbon center with MeOC(=O) and CH2=CH groups in axial and equatorial positions. The MeOC(=O) group was transformed to the Me group to complete the synthesis of cyclobakuchiol B.


Asunto(s)
Antiinflamatorios/síntesis química , Ciclohexanos/síntesis química , Fenoles/síntesis química , Antiinflamatorios/química , Monoterpenos Bicíclicos , Compuestos Bicíclicos con Puentes/química , Ciclohexanos/química , Ciclohexanonas/química , Compuestos Epoxi/química , Esterificación , Monoterpenos/química , Fenoles/química , Psoralea/química , Psoralea/metabolismo , Estereoisomerismo
20.
Biosci Biotechnol Biochem ; 78(4): 647-50, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25036962

RESUMEN

OPDA (12-oxo-phytodienoic acid) not only is an intermediate in jasmonic acid biosynthesis but also regulates gene expression, although mechanisms of OPDA-induced signaling are largely unknown. Here, we measured transcriptional responses of the OPDA-responsive genes HsfA2 and DREB2A to the protein synthesis inhibitor cycloheximide and to the HSP90 inhibitor geldanamycin. The results suggest that HSP90 and other proteins suppress the expression.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Unión al ADN/genética , Ácidos Grasos Insaturados/farmacología , Proteínas de Choque Térmico/genética , Proteínas de Plantas/genética , Estrés Fisiológico/efectos de los fármacos , Factores de Transcripción/genética , Activación Transcripcional/efectos de los fármacos , Arabidopsis/citología , Arabidopsis/efectos de los fármacos , Benzoquinonas/farmacología , Cicloheximida/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Factores de Transcripción del Choque Térmico , Lactamas Macrocíclicas/farmacología , Transducción de Señal/efectos de los fármacos , Transcripción Genética/efectos de los fármacos
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