Stereocontrolled synthesis of resolvin D1.

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.

Stereocontrolled Synthesis of Resolvin D4.

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.

Stereoselective Total Synthesis of Macrophage-Produced Prohealing 14,21-Dihydroxy Docosahexaenoic Acids.

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.

Total Synthesis of Resolvin D5.

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.

Stereoselective synthesis of 17,18-epoxy derivative of EPA and stereoisomers of isoleukotoxin diol by ring opening of TMS-substituted epoxide with dimsyl sodium.

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.

Asymmetric synthesis of 12-hydroxyheptadecatrienoic acid and its 5,6-dihydro- and 14,15-dehydro-derivatives.

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.

Laparoscopic Cholecystectomy for a Patient with Left-sided Gallbladder.

A 47-year-old man who presented with epigastric pain after a meal was diagnosed with biliary sludge present in the gallbladder. Endoscopic retrograde cholangiopancreatography showed normal anatomy of the biliary tree. During the exploratory phase of a laparoscopic cholecystectomy using four ports positioned as usual, surgeons observed a left-sided gallbladder. A review of the preoperative imaging by computed tomography confirmed a round ligament connected to the right portal umbilical portion. It also established that the gallbladder was located to the left of the round ligament, and attached to the left lateral segment of the liver. Laparoscopic cholecystectomy was performed successfully in this patient with the usual port site and careful dissection with a normograde approach. The patient was discharged on the second postoperative day with an uneventful course. Prior identification of a left-sided gallbladder is possible with cautious attention. In particular, it is important for the surgeon to be aware of unusual alterations in the portal and biliary anatomy associated with this anomaly to safely complete a laparoscopic cholecystectomy.

Lysosomal lipid peroxidation regulates tumor immunity.

Lysosomal inhibition elicited by palmitoyl-protein thioesterase 1 (PPT1) inhibitors such as DC661 can produce cell death, but the mechanism for this is not completely understood. Programmed cell death pathways (autophagy, apoptosis, necroptosis, ferroptosis, and pyroptosis) were not required to achieve the cytotoxic effect of DC661. Inhibition of cathepsins, or iron or calcium chelation, did not rescue DC661-induced cytotoxicity. PPT1 inhibition induced lysosomal lipid peroxidation (LLP), which led to lysosomal membrane permeabilization and cell death that could be reversed by the antioxidant N-acetylcysteine (NAC) but not by other lipid peroxidation antioxidants. The lysosomal cysteine transporter MFSD12 was required for intralysosomal transport of NAC and rescue of LLP. PPT1 inhibition produced cell-intrinsic immunogenicity with surface expression of calreticulin that could only be reversed with NAC. DC661-treated cells primed naive T cells and enhanced T cell-mediated toxicity. Mice vaccinated with DC661-treated cells engendered adaptive immunity and tumor rejection in "immune hot" tumors but not in "immune cold" tumors. These findings demonstrate that LLP drives lysosomal cell death, a unique immunogenic form of cell death, pointing the way to rational combinations of immunotherapy and lysosomal inhibition that can be tested in clinical trials.

Linear regression models predicting strength of transcriptional activity of promoters.

We developed linear regression models which predict strength of transcriptional activity of promoters from their sequences. Intrinsic transcriptional strength data of 451 human promoter sequences in three cell lines (HEK293, MCF7 and 3T3), which were measured by systematic luciferase reporter gene assays, were used to build the models. The models sum up contributions of CG dinucleotide content and transcription factor binding sites (TFBSs) to transcriptional strength. We evaluated prediction accuracies of the models by cross validation tests and found that they have adequate ability for predicting transcriptional strength of promoters in spite of their simple formalization. We also evaluated statistical significance of the contributions and proposed a picture of regulatory code hidden in promoter sequences. That is, CG dinucleotide content and TFBSs mainly determine strength of transcriptional activity under ubiquitous and specific environments, respectively.

Syntheses of secocyclolignanes and comparative antioxidative activity between secocyclolignane and the dibenzyl type of lignan.

The antioxidative activity of secocyclolignanes was compared with that of the corresponding dibenzyl lignans for the first time. The radical scavenging activity of the secocyclolignanes was weaker than that of the corresponding dibenzyl lignans, the butane diol type showing the highest activity. The butane type of secocyclolignane exhibited the highest antioxidant activity of the unsaturated fatty acid.

First diastereoselective construction of butane-type and butyrolactone-type secocyclolignane structures.

The first diastereoselective construction of butane-type and butyrolactone-type secocyclolignanes was achieved by the application of a high-valency heterobimetallic Ir-Sn complex to benzyl alcohols prepared from an Evans's anti-aldol product. The elimination of an acetoxymethyl group to give a cinnamyl structure by using a high-valency heterobimetallic Ir-Sn complex was also observed in this study.

Use of the 2-Pyridinesulfonyloxy Leaving Group for the Fast Copper-Catalyzed Coupling Reaction at Secondary Alkyl Carbons with Grignard Reagents.

Investigation of the copper-catalyzed coupling reaction of 2-pyridinesulfonates with Grignard reagents revealed that reactions with catalytic Cu(OTf)2 were completed in <40 min. The results differed from those of the previous CuI-catalyzed reactions of tosylates in the presence of additives (LiOMe and TMEDA) for 12-24 h. It was shown that the preferred coordination of the leaving group to the reagents accelerated the reaction. Successful reagents were MeMgCl and other RMgX. Complete inversion was established.

Stereoselective Synthesis of Maresin-like Lipid Mediators.

Maresin-L1 (14S,22-dihydroxy-docosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid) and maresin-L2 (14R,22-dihydroxy-docosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid) were chemically synthesized. They were identical to activated macrophage produced counterparts and their total synthesis was highly Stereoselective, as revealed by chiral LC-UV-MS/MS analysis. The synthesis involved the following steps: (1) kinetic resolution of a racemic allylic alcohol by the asymmetric epoxidation; (2) transformation of the epoxy alcohol to γ-hydroxyenal derivative; and (3) the Wittig reaction to furnish the Z-olefin.

Alkylation of active methylene compounds with alcohols catalyzed by an iridium complex.

Base-free catalytic alpha-alkylation of active methylene compounds with primary alcohols was successfully achieved using an [IrCl(cod)](2) complex in the presence of PPh(3) to afford the corresponding saturated alpha-alkylated products in good yields.

Sorption mechanisms of chromate with coprecipitated ferrihydrite in aqueous solution.

Hexavalent chromium (Cr(VI)) attracted researchers' interest for its toxicity, natural availability and removal difficulty. Nevertheless, its sorption mechanism is not clearly understood yet. In this work, we elucidated the sorption mechanism of the co-precipitation of chromates with ferrihydrite through quantitative analysis. The influence of Cr/Fe molar ratio on sorption was investigated by zeta potential measurements, X-ray diffraction (XRD) and X-ray adsorption fine-structure analysis (XAFS). Coprecipitation at pH 5 showed almost twice the sorption density of adsorption at pH 5. In co-precipitation, a shift of the XRD peak due to inner-sphere sorption of chromate was observed at Cr/Fe molar ratio 0.5. For adsorption, the same peak shift was confirmed at Cr/Fe molar ratio of 1. Zeta potential at pH 5 suggested that the sorption mechanism changed at Cr/Fe molar ratio 0.25 for coprecipitation and at Cr/Fe molar ratio of 1 for adsorption. Fitting of Cr and Fe K-edge extended X-ray adsorption fine-structure suggested that ferrihydrite immobilized Cr(VI) via outer sphere surface complexation for lower Cr/Fe ratios and via inner-sphere surface complexation for higher molar ratios. At higher molar ratios, bidentate binuclear CrFe bonds were well established, thus resulting in the expansion of the ferrihydrite structure.

Total Syntheses of Perenniporides.

The total syntheses of perenniporide A (1) and related compounds have been achieved. Starting from 1,3,5-trifluorobenzene (9), difluorodienone 6 was obtained by oxidative dearomatization, which served as a platform for the high-pressure cycloaddition and for the introduction of the C3-methoxy group. The synthesis allowed access to the natural congeners 2 and 3, enabling assignment of the absolute structures of these natural products.

Synthesis and electrolytic polymerization of the ethylenedioxy-substituted terthiophene-fullerene dyad.

[reaction: see text] Two derivatives of ethylenedioxy-substituted terthiophene-fullerene dyads were newly synthesized as the precursors for polythiophene having fullerene side chains. By electrolytic oxidation of dyad 1, the charm-bracelet type polythiophene, poly-1, was obtained as a purple film, which showed electrochemical activity, electrochromism, and photoelectronic response.

Population study of expression of thymidylate synthase and dihydropyrimidine dehydrogenase in patients with solid tumors.

Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) has been suggested to be sensitivity-limiting factors of 5-fluorouracil therapy in cancer patients. We conducted a large-scale population study on the activity of TS and DPD in patients with various solid tumors. A total of 2590 clinically removed tumors, consisting of 1112 colon, 724 gastric, 520 breast, and 236 non-small cell lung cancers, were provided to measure TS and DPD activity. TS activity in the gastric, colon, and non-small cell lung cancers was significantly higher than in matched non-cancerous tissue (P<0.0002), but there was no difference in TS expression between tumor and non-cancerous tissue from breast cancer patients. Gastric, breast, and non-small cell lung cancers showed significantly higher DPD activity than their corresponding non-cancerous tissues, but colon cancers did not. There was no correlation between TS activity and DPD activity, and thus each enzyme was considered to be an independent sensitivity-limiting factor for 5-fluorouracil therapy. The median TS activity and median DPD activity in all specimens including gastric, colorectal, breast, and non-small cell lung cancers tested were 0.041 and 110.1 pmol/mg protein, respectively. We classified each of the type of carcinoma into 4 groups by using the median activity of TS and DPD as the cutoff values: a low TS/low DPD group, high TS/low DPD group, low TS/high DPD group, and high TS/high DPD group. About 50% of the gastric, 47% of the colon, 70% of the breast and 30% of the non-small cell lung cancers had high TS activity, and 60% of the gastric, 40% of the colon, 48% of the breast, and 87% of the lung cancers had high DPD activity. Moreover, breast cancer was characterized by high TS activity and lung cancer by high DPD activity as compared with gastric and colon cancers, and their high activity levels may influence to the effectiveness of 5-fluorouracil against cancers of these organs. The results for expression of TS and DPD in clinically dissected tumors would be useful to estimate the efficacy of 5-fluorouracil in the treatment of cancer patients.

One-Pot synthesis of gamma,delta-unsaturated carbonyl compounds from allyl alcohols and vinyl or isopropenyl acetates catalyzed by [IrCl(cod)]2.

One-pot synthesis of gamma,delta-unsaturated carbonyl compounds from allyl alcohols and vinyl or isopropenyl acetates was achieved through in situ generation of allyl vinyl ethers by the action of the [IrCl(cod)]2 complex followed by Claisen rearrangement of the resulting ethers. For instance, the reaction of trans-2-methyl-3-phenyl-2-propen-1-ol with isopropenyl acetate in the presence of [IrCl(cod)]2 (1 mol %) and Cs2CO3 (5 mol %) at 100 degrees C for 3 h followed by 140 degrees C for 15 h afforded 5-methyl-4-phenyl-5-hexen-2-one in 72% yield. When vinyl acetate was employed in place of isopropenyl acetate, 4-methyl-3-phenyl-4-pentenal was obtained in 83% yield.