- Photoredox Activation of Formate Salts: Hydrocarboxylation of Alkenes via Carboxyl Group Transfer
-
A photoredox activation mode of formate salts for carboxylation was developed. Using a formate salt as the reductant, carbonyl source, and hydrogen atom transfer reagent, a wide range of alkenes can be converted into acid products via a carboxyl group tra
- Huang, Yan,Hou, Jing,Zhan, Le-Wu,Zhang, Qian,Tang, Wan-Ying,Li, Bin-Dong
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p. 15004 - 15012
(2021/12/14)
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- Photoinduced Hydrocarboxylation via Thiol-Catalyzed Delivery of Formate across Activated Alkenes
-
Herein we disclose a new photochemical process to prepare carboxylic acids from formate salts and alkenes. This redox-neutral hydrocarboxylation proceeds in high yields across diverse functionalized alkene substrates with excellent regioselectivity. This operationally simple procedure can be readily scaled in batch at low photocatalyst loading (0.01% photocatalyst). Furthermore, this new reaction can leverage commercially available formate carbon isotologues to enable the direct synthesis of isotopically labeled carboxylic acids. Mechanistic studies support the working model involving a thiol-catalyzed radical chain process wherein the atoms from formate are delivered across the alkene substrate via CO2?- as a key reactive intermediate.
- Alektiar, Sara N.,Wickens, Zachary K.
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supporting information
p. 13022 - 13028
(2021/09/03)
-
- Molecular umbrella as a nanocarrier for antifungals
-
A molecular umbrella composed of two O‐sulfated cholic acid residues was applied for the construction of conjugates with cispentacin, containing a “trimethyl lock” (TML) or o‐dithiobenzylcarbamoyl moiety as a cleavable linker. Three out of five conjugates
- Skwarecki, Andrzej S.,Martynow, Dorota,Milewska, Maria J.,Milewski, S?awomir
-
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- SUBSTITUTED 3-ISOBUTYL-9,10-DIMETHOXY-1,3,4,6,7,11B-HEXAHYDRO-2H-PYRIDO[2,1-a]ISOQUINOLIN-2-OL COMPOUNDS, THEIR SYNTHESIS, AND USE THEREOF
-
The invention relates to substituted 3-isobutyl-9,10-dimethoxy-1,3,4,6,7,11b-hexahydro-2H-pyrido[2,1-a]isoquinolin-2-ol compounds, their synthesis, pharmaceutical compositions containing them, and methods of using them in the treatment of disorders benefiting from inhibition of vesicular monoamine transporter 2 (VMAT2).
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-
Paragraph 0194-0195
(2021/04/02)
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- CYCLIC TETRAMER COMPOUNDS AS PROPROTEIN CONVERTASE SUBTILISIN/KEXIN TYPE 9 (PCSK9) INHIBITORS FOR THE TREATMENT OF METABOLIC DISORDERS
-
The disclosure relates to inhibitors of PCSK9 useful in the treatment of cholesterol lipid metabolism, and other diseases in which PCSK9 plays a role, having the Formula (I): or a pharmaceutically acceptable salt, hydrate, solvate, prodrug, stereoisomer, N-oxide, or tautomer thereof, wherein R1, R1, R1, R1, R1, R1, R1, R1, R1, X1, X2, and X3 are described herein.
- -
-
Paragraph 0666; 0669; 0670
(2020/06/16)
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- Hydrosilane-Promoted Facile Deprotection of tert-Butyl Groups in Esters, Ethers, Carbonates, and Carbamates
-
Combination of PdCl2 with 1,1,3,3-tetramethyldisiloxane in the presence of activated carbon was found to be an effective catalyst system for the cleavage reaction of C?O bond of O?t-Bu moieties. The present catalytic reaction offers a practical method for the deprotection of tert-butyl esters, tert-butyl ethers, O-Boc, and N-Boc derivatives under mild conditions. The addition of activated carbon in the reaction mixture was proved to be crucial for not only sustaining the catalytic activity but also trapping the palladium species after the reaction. (Figure presented.).
- Ikeda, Takuya,Zhang, Zhenzhong,Motoyama, Yukihiro
-
supporting information
p. 673 - 677
(2019/01/04)
-
- A MedChem toolbox for cereblon-directed PROTACs
-
A modular chemistry toolbox was developed for cereblon-directed PROTACs. A variety of linkers was attached to a CRBN ligand via the 4-amino position of pomalidomide. We used linkers of different constitution to modulate physicochemical properties. We equipped one terminus of the linker with a set of functional groups, e.g. protected amines, protected carboxylic acids, alkynes, chloroalkanes, and protected alcohols, all of which are considered to be attractive for PROTAC design. We also highlight different opportunities for the expansion of the medicinal chemists' PROTAC toolbox towards heterobifunctional molecules, e.g. with biotin, fluorescent, hydrophobic and peptide tags.
- Steinebach, Christian,Sosi?, Izidor,Lindner, Stefanie,Bricelj, Ale?a,Kohl, Franziska,Ng, Yuen Lam Dora,Monschke, Marius,Wagner, Karl G.,Kr?nke, Jan,Gütschow, Michael
-
supporting information
p. 1037 - 1041
(2019/06/27)
-
- Control of conformation in α-helix mimicking aromatic oligoamide foldamers through interactions between adjacent side-chains
-
The design, synthesis and structural characterization of non-natural oligomers that adopt well-defined conformations, so called foldamers, is a key objective in developing biomimetic 3D functional architectures. For the aromatic oligoamide foldamer family
- Arrata, Irene,Grison, Claire M.,Coubrough, Heather M.,Prabhakaran, Panchami,Little, Marc A.,Tomlinson, Darren C.,Webb, Michael E.,Wilson, Andrew J.
-
supporting information
p. 3861 - 3867
(2019/04/26)
-
- Bisubstrate inhibitors of nicotinamide N-methyltransferase (NNMT) with enhanced activity
-
Nicotinamide N-methyltransferase (NNMT) catalyzes the methylation of nicotinamide to form N-methylnicotinamide. Overexpression of NNMT is associated with a variety of diseases, including a number of cancers and metabolic disorders, suggesting a role for NNMT as a potential therapeutic target. By structural modification of a lead NNMT inhibitor previously developed in our group, we prepared a diverse library of inhibitors to probe the different regions of the enzyme's active site. This investigation revealed that incorporation of a naphthalene moiety, intended to bind the hydrophobic nicotinamide binding pocket via π-πstacking interactions, significantly increases the activity of bisubstrate-like NNMT inhibitors (half-maximal inhibitory concentration 1.41 μM). These findings are further supported by isothermal titration calorimetry binding assays as well as modeling studies. The most active NNMT inhibitor identified in the present study demonstrated a dose-dependent inhibitory effect on the cell proliferation of the HSC-2 human oral cancer cell line.
- Gao, Yongzhi,Van Haren, Matthijs J.,Moret, Ed E.,Rood, Johannes J. M.,Sartini, Davide,Salvucci, Alessia,Emanuelli, Monica,Craveur, Pierrick,Babault, Nicolas,Jin, Jian,Martin, Nathaniel I.
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p. 6597 - 6614
(2019/08/20)
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- POLY-ADP RIBOSE POLYMERASE (PARP) INHIBITORS
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The present invention is related to a pharmaceutical composition comprising a pharmaceutically acceptable carrier or diluent and a compound represented by the following structural formula: The present invention is also related a method of treating a subject with a disease which can be ameliorated by inhibition of poly(ADP-ribose)polymerase (PARP). The definitions of the variables are provided herein.
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Page/Page column 103
(2018/07/29)
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- dM-Dim for carboxylic acid protection
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The 1,3-dithian-2-yl-methyl (Dim) and its analogous groups including dimethyl-Dim (dM-Dim) can provide a new dimension of orthogonality for carboxylic acid protection. They can be deprotected under nearly neutral oxidative conditions. In this paper, the protection of carboxylic acid with dM-Dim, deprotection of dM-Dim ester with sodium periodate, stability of dM-Dim protected carboxylic acid under acidic and basic conditions, and selective deprotection of dM-Dim protected carboxylic acids in the presence of tertiary butyl and methyl esters are presented.
- Shahsavari, Shahien,Wigstrom, Travis,Gooding, James,McNamara, Chase,Fang, Shiyue
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p. 1763 - 1766
(2018/04/06)
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- Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics
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The amide moiety of peptides can be replaced for example by a triazole moiety, which is considered to be bioisosteric. Therefore, the carbonyl moiety of an amino acid has to be replaced by an alkyne in order to provide a precursor of such peptidomimetics. As most amino acids have a chiral center at Cα, such amide bond surrogates need a chiral moiety. Here the asymmetric synthesis of a set of 24 N-sulfinyl propargylamines is presented. The condensation of various aldehydes with Ellman's chiral sulfinamide provides chiral N-sulfinylimines, which were reacted with (trimethylsilyl)ethynyllithium to afford diastereomerically pure N-sulfinyl propargylamines. Diverse functional groups present in the propargylic position resemble the side chain present at the Cα of amino acids. Whereas propargylamines with (cyclo)alkyl substituents can be prepared in a direct manner, residues with polar functional groups require suitable protective groups. The presence of particular functional groups in the side chain in some cases leads to remarkable side reactions of the alkyne moiety. Thus, electron-withdrawing substituents in the Cα-position facilitate a base induced rearrangement to α,β-unsaturated imines, while azide-substituted propargylamines form triazoles under surprisingly mild conditions. A panel of propargylamines bearing fluoro or chloro substituents, polar functional groups, or basic and acidic functional groups is accessible for the use as precursors of peptidomimetics.
- Wünsch, Matthias,Schr?der, David,Fr?hr, Tanja,Teichmann, Lisa,Hedwig, Sebastian,Janson, Nils,Belu, Clara,Simon, Jasmin,Heidemeyer, Shari,Holtkamp, Philipp,Rudlof, Jens,Klemme, Lennard,Hinzmann, Alessa,Neumann, Beate,Stammler, Hans-Georg,Sewald, Norbert
-
supporting information
p. 2428 - 2441
(2017/12/06)
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- A Versatile Approach for Site-Specific Lysine Acylation in Proteins
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Using amber suppression in coordination with a mutant pyrrolysyl-tRNA synthetase-tRNAPylpair, azidonorleucine is genetically encoded in E. coli. Its genetic incorporation followed by traceless Staudinger ligation with a phosphinothioester allows the convenient synthesis of a protein with a site-specifically installed lysine acylation. By simply changing the phosphinothioester identity, any lysine acylation type could be introduced. Using this approach, we demonstrated that both lysine acetylation and lysine succinylation can be installed selectively in ubiquitin and synthesized histone H3 with succinylation at its K4 position (H3K4su). Using an H3K4su-H4 tetramer as a substrate, we further confirmed that Sirt5 is an active histone desuccinylase. Lysine succinylation is a recently identified post-translational modification. The reported technique makes it possible to explicate regulatory functions of this modification in proteins.
- Wang, Zhipeng A.,Kurra, Yadagiri,Wang, Xin,Zeng, Yu,Lee, Yan-Jiun,Sharma, Vangmayee,Lin, Hening,Dai, Susie Y.,Liu, Wenshe R.
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supporting information
p. 1643 - 1647
(2017/02/05)
-
- BIO-INSPIRED AND ANTIMICROBIAL POLYMERS CONTAINING AMINO ACID-LIKE MONOMER BUILDING BLOCKS
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Methods for killing a microbial are provided that include introducing a functionalized amide polymer to a microbe, where the functionalized amide polymer includes a polymer backbone selected from polyesters and polyurethanes; an amide group with a pendant functional group, where the nitrogen atom of the amide group is part of the polymer backbone; and a net positive charge.
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-
Paragraph 0081
(2017/07/14)
-
- Cisplatin-Stitched Polysaccharide Vesicles for Synergistic Cancer Therapy of Triple Antagonistic Drugs
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New cisplatin-stitched polysaccharide vesicular nanocarrier is developed for combination therapy of three clinical important antagonistic drugs together to accomplish synergistic cancer therapy in breast cancer treatment. Carboxylic functionalized dextran was tailor-made for the chemical conjugation of cisplatin, and a renewable hydrophobic unit was anchored in the backbone to interdigitize the chains to self-assemble as cisplatin-stitched polysaccharide nanovesicles. Water-soluble DNA-intercalating drug doxorubicin·HCl (DOX) and water insoluble topoisomerase type I inhibitor drug camptothecin (CPT) were encapsulated in these vesicles to produce dual or triple drug-loaded vesicular nanocarrier. This unique cisplatin, DOX and CPT triple drug-loaded dextran vesicles were stable in aqueous medium, and the vesicular geometry acted as a shield for Pt-polymer drug conjugate against glutathione (GSH) detoxification under physiological conditions. Lysosomal enzymes ruptured the nanovesicle exclusively at the intracellular compartments to deliver the combination of all three drugs simultaneously to maximize the therapeutic efficacies. In vitro cytotoxicity studies revealed that free cisplatin was highly detoxified by the GSH in breast cancer cells, whereas the enhanced stability of Pt-stitched dextran vesicle against GSH facilitated ~99% cell killing in breast cancer cells. Combination therapy studies revealed that the free cisplatin, DOX, and CPT were found to be antagonistic to each other. Dual drug-loaded vesicles exhibited synergistic cancer cell killing while delivering these antagonistic drugs from a dextran vesicular platform. Remarkable synergistic cell killing was accomplished in cisplatin, DOX, and CPT triple drug-loaded vesicles at nanogram concentrations in breast cancer cells. The internalization of drugs and cellular uptake were confirmed by confocal microscope and flow cytometry analysis. The drugs were taken by the cancer cells in large amounts while delivering them from dextran vesicles compared to their free form. These spectacular results opened new opportunities for synergistic cancer therapy for GSH-overexpressed breast cancer using triple drug-loaded polysaccharide vesicular nanocarriers.
- Deshpande, Nilesh Umakant,Jayakannan, Manickam
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p. 113 - 126
(2017/04/26)
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- Synthesis of d-labeled and unlabeled ethyl succinic anhydrides and application to quantitative analysis of peptides by isotope differential mass spectrometry
-
Ethyl succinic anhydride and its d5-labeled version have been synthesized and applied to quantitative analysis of peptides in combination with MALDI or ESI mass spectrometry. These modifiers react with amino groups in the N-termini and lysine side chains in proteins, and therefore the combination of these modifiers was shown to be a useful tool for quantification of peptides and hence for proteomics research.
- Niwayama, Satomi,Zabet-Moghaddam, Masoud,Kurono, Sadamu,Kattanguru, Pullaiah,Shaikh, Aarif L.
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p. 5073 - 5077
(2016/10/04)
-
- Synthesis and anticancer properties of RGD peptides conjugated to nitric oxide releasing functional groups and abiraterone
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A series of analogues of the integrin binding aspartic acid-glycine-arginine (RGD) peptide sequence were synthesised conjugated to nitric oxide (NO) donating functional groups. Also the cytotoxicity of abiraterone, a prostate cancer drug, was explored when it was conjugated in three part constructs to RGD sequences and NO releasing heterocycles. In general the analogues showed integrin binding affinity comparable to RGD reference compounds, and all released NO by the Griess test assay. Two analogues exhibited significant cytotoxic effects against PC3 and MCF7 cell lines.
- Nortcliffe, Andrew,Fleming, Ian N.,Botting, Nigel P.,O'Hagan, David
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supporting information
p. 8343 - 8347
(2015/03/05)
-
- Synthesis and biological evaluation (in Vitro and in Vivo) of cyclic arginine-glycine-aspartate (RGD) peptidomimetic-paclitaxel conjugates targeting integrin αvβ3
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A small library of integrin ligand-paclitaxel conjugates 10-13 was synthesized with the aim of using the tumor-homing cyclo[DKP-RGD] peptidomimetics for site-directed delivery of the cytotoxic drug. All the paclitaxel-RGD constructs 10-13 inhibited biotinylated vitronectin binding to the purified αVβ3 integrin receptor at low nanomolar concentration and showed in vitro cytotoxic activity against a panel of human tumor cell lines similar to that of paclitaxel. Among the cell lines, the cisplatin-resistant IGROV-1/Pt1 cells expressed high levels of integrin αVβ3, making them attractive to be tested in in vivo models. cyclo[DKP-f3-RGD]-PTX 11 displayed sufficient stability in physiological solution and in both human and murine plasma to be a good candidate for in vivo testing. In tumor-targeting experiments against the IGROV-1/Pt1 human ovarian carcinoma xenotransplanted in nude mice, compound 11 exhibited a superior activity compared with paclitaxel, despite the lower (about half) molar dosage used.
- Colombo, Raffaele,Mingozzi, Michele,Belvisi, Laura,Arosio, Daniela,Piarulli, Umberto,Carenini, Nives,Perego, Paola,Zaffaroni, Nadia,De Cesare, Michelandrea,Castiglioni, Vittoria,Scanziani, Eugenio,Gennari, Cesare
-
supporting information
p. 10460 - 10474
(2013/02/22)
-
- 4-HYDROXYBUTYRIC ACID ANALOGS
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This invention relates to novel derivatives of 4-hydroxybutyric acid and prodrugs thereof, and pharmaceutically acceptable salts of the foregoing. This invention also provides pharmaceutical compositions comprising a compound of this invention and the use of such compositions in methods of treating narcolepsy, fibromyalgia, other disorders or conditions that are beneficially treated by improving nocturnal sleep or by administering sodium oxybate.
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Page/Page column 28
(2010/11/05)
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- Design and in vitro evaluation of branched peptide conjugates: Turning nonspecific cytotoxic drugs into tumor-selective agents
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The use of peptide receptors as targets for tumor-selective therapies was envisaged years ago with the findings that receptors for different endogenous regulatory peptides are overexpressed in several primary and metastatic human tumors, and can be used as tumor antigens. Branched peptides can retain or even increase, through multivalent binding, the biological activity of a peptide and are very resistant to proteolysis, thus having a markedly higher in vivo activity compared with the corresponding monomeric peptides. Oligo-branched peptides, containing the human regulatory peptide neurotensin (NT) sequence, have been used as tumor-specific targeting agents. These peptides are able to selectively and specifically deliver effector units, for cell imaging or killing, to tumor cells that overexpress NT receptors. Results obtained with branched NT conjugated to different functional units for tumor imaging and therapy indicate that branched peptides are promising novel multifunctional targeting molecules. This study is focused on the role of the releasing pattern of drug-conjugated branched NT peptides. We present results obtained with oligobranched neurotensin peptides conjugated to 6-mercaptopurin (6-MP), combretastain A-4 (CA4) and monastrol (MON). Drugs were conjugated to oligo-branched neurotensin through different linkers, and the mode-of-release, together with cytotoxicity, was studied in different human cancer cell lines. The results show that branched peptides are very promising pharmacodelivery options. Among our drug-armed branched peptides, NT4-CA4 was identified as a candidate for further development and evaluation in preclinical pharmacokinetic and pharmacodynamic studies. This peptide-drug exhibits significant activity against pancreas and prostate human cancer cells. Consequently, this derivative is of considerable interest due to the high mortality rates of pancreas neuroendocrine tumors and the high incidence of prostate cancer.
- Falciani, Chiara,Brunetti, Jlenia,Pagliuca, Chiara,Menichetti, Stefano,Vitellozzi, Lucia,Lelli, Barbara,Pini, Alessandro,Bracci, Luisa
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scheme or table
p. 567 - 574
(2010/12/18)
-
- (1-Nosyl-5-nitroindol-3-yl)methyl ester: A novel protective group for carboxylic acids
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(Chemical Equation Presented) The usefulness of (1-nosyl-5-nitroindol-3-yl) methyl esters as a novel protective group for carboxylic acid is fully demonstrated. The novel protective group is stable under a broad range of conditions and can easily be deprotected under the mild conditions used for removal of the nosyl (Ns) group. It is orthogonal to the existing protective groups for carboxylic acids such as t-butyl and allyl esters.
- Nishimura, Takuya,Yamada, Kouhei,Takebe, Tohru,Yokoshima, Satoshi,Fukuyama, Tohru
-
supporting information; experimental part
p. 2601 - 2604
(2009/05/26)
-
- Synthesis and DNA-cleaving activity of lactenediynes conjugated with DNA-complexing moieties
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Lactenediynes are compounds characterized by the fusion of a β-lactam with a cyclodeca-3-ene-1,5-diyne. In this work the most promising members of this family have been activated by attaching a carbalkoxy or a carbamoyl group to the azetidinone nitrogen, and conjugated to various DNA-complexing moieties, either acting by intercalation or through groove binding. These conjugated artificial enediynes have been demonstrated to possess in vitro ability to produce single and double strand cleavage of plasmid DNA. As potency and capacity to induce double cut, they rank among the best simple enediyne analogues ever prepared. A thorough investigation was carried out in order to develop the best suited linkers for assembling these conjugates.
- Banfi, Luca,Basso, Andrea,Bevilacqua, Elisabetta,Gandolfo, Valentina,Giannini, Giuseppe,Guanti, Giuseppe,Musso, Loana,Paravidino, Monica,Riva, Renata
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p. 3501 - 3518
(2008/09/21)
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- Rapid assembly and in situ screening of bidentate inhibitors of protein tyrosine phosphatases
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We have successfully designed and synthesized a small library of protein tyrosine phosphatase (PTP) inhibitors, in which the so-called "click chemistry" or Cu(I)-catalyzed 1,3-dipolar alkyne-azide coupling reaction was carried out for rapid assembly of 66 different bidentate compounds. Subsequent in situ enzymatic screening revealed a potential PTP1B inhibitor (IC50 = 4.7 μM) which is 10-100 fold more potent than other PTPs.
- Srinivasan, Rajavel,Uttamchandani, Mahesh,Yao, Shao Q.
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p. 713 - 716
(2007/10/03)
-
- A prodrug system for hydroxylamines based on esterase catalysis
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The synthesis and reactivity of hydroxy hydroxamates as models for a prodrug form of hydroxylamine are described. γ-Hydroxy hydroxamates were found to enable hydroxylamine release via lactonisation. Hydroxamates were found to undergo esterase catalysed hydrolysis.
- Conejo-Garcia, Ana,Schofield, Christopher J.
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p. 4004 - 4009
(2007/10/03)
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- Enantioselective preparation of β2-amino acids with aspartate, glutamate, asparagine, and glutamine side chains
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(S)-β2-Homoamino acids with the side chains of Asp, Glu, Asn, and Gln have been prepared and suitably protected (N-Fmoc, CO 2′Bu CONHTrt) for solid-phase peptide syntheses. The key steps of the syntheses are: N-acylation of 5,5-diphe
- Lelais, Gerald,Campo, Marino A.,Kopp, Sascha,Seebach, Dieter
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p. 1545 - 1560
(2007/10/03)
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- Synthesis of a new conformation-constrained L-tyrosine analogue as a potential scaffold for SH2 domain ligands
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The enantioselective synthesis of a new tricyclic tyrosine analogue is reported. This conformation-contrained SH2 domain ligand scaffold 2 was designed on the basis of the natural ligand, whose structure contains the elements of a tyrosine moiety having χ1 and χ2 angles constrained to values observed for a phosphotyrosyl (pTyr) residue bound to the p56lck SH2 domain. It represents a unique, highly constrained amino acid, which may be of value in signal transduction studies. Three key steps, an asymmetric tandem Michael addition, an intramolecular Friedel-Crafts reaction, and an intramolecular Mannich reaction, were successfully applied in the presented synthetic route.
- Liu, Fa,Zha, Hui-Yan,Yao, Zhu-Jun
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p. 6679 - 6684
(2007/10/03)
-
- Nonactin biosynthesis: The initial committed step is the condensation of acetate (malonate) and succinate
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Nonactin is a macrotetrolide antibiotic produced by Streptomyces griseus subsp. griseus ETH A7796 that has shown activity against the P170-glycoprotein efflux pump associated with multiple drug resistant cancer cells. Nonactin is a polyketide, albeit a highly atypical one. The structure is composed of two units of each of the enantiomers of nonactic acid, arranged in a macrocycle, so that the molecule has S4 symmetry and is achiral. The monomer units, (+)- and (-)-nonactic acid, are derived from acetate, succinate, and propionate, although the exact details of the assembly process are quite unclear. We have used feeding experiments with a series of multiple stable isotope labeled precursors to elucidate the details of the first committed step of nonactic acid biosynthesis. We have found that the 13C label from 3-ketoadipate is incorporated specifically into both nonactic acid and its homologue, homononactic acid. The data conclusively show that the first committed step of nonactin biosynthesis is the coupling of a succinate derivative with either acetate or malonate. The differentiation into either nonactate or homononactate occurs after the initial condensation; the homologues are not derived from use of a different "starter unit" by the nonactate polyketide synthase. The first step of nonactin biosynthesis involves achiral intermediates; differentiation between the known enantiocomplementary biosynthesis pathways to form each enantiomer of the precursor monomer units likely occurs after the initial condensation reaction.
- Nelson, Michael E.,Priestley, Nigel D.
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p. 2894 - 2902
(2007/10/03)
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- Low molecular weight peptide derivatives as inhibitors of the laminin/nidogen interaction
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Low molecular weight peptide derivatives which are able to act as inhibitors of the interaction between laminin and nidogen (laminin/nidogen interaction), a process for their preparation, pharmaceutical compositions prepared therefrom and their use for preparing pharmaceuticals and for identifying inhibitors of the laminin/nidogen interaction.
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-
- Trigger lipids inducing pH-dependent liposome fusion
-
Aspartic acid-derived artificial lipids (ADLs; s indicates the number of the methylene groups, s=2, 4, 6, 8, 10, 12) (Scheme 1) with various carboxyl alkyl chains as head groups are designed and synthesized, which are incorporated into liposome membranes by sonication. Fluorescence resonance energy transfer (FRET) measurements indicate that ADL6, ADL8 and ADL10 have high lipid-mixing ability in the acidic solution. The other ADLs, however, do not induce remarkable liposome fusion at acidic nor neutral pH. The hydrophobicity of the head groups of ADL6, ADL8 and ADL10 is suitable as triggers of membrane fusion.
- Ogawa, Yoshikatsu,Kodaka, Masato,Okuno, Hiroaki
-
-
- Synthesis of monosubstituted succinic acids from tert-butylsuccinate
-
We report the preparation and alkylation of the dianion of t-butylsuccinate. This alkylation reaction has proven to be a useful method for the preparation of monosubstituted succinic acids and anhydrides.
- Bergmeier,Ismail
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p. 1369 - 1371
(2007/10/03)
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- Non-peptidic liposome-fusion compounds at acidic pH
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Liposomes including aspartic acid-derived artificial lipids (ADL) with various carboxy alkyl chains as head groups (ADLn; n indicates the number of the methylene groups, n = 2,4,6,8,10,12) are prepared, in which ADL6 and ADL8 liposomes induce remarkably high lipid-mixing in the acidic region.
- Ogawa, Yoshikatsu,Tomohiro, Takenori,Yamazaki, Yoshimitsu,Kodaka, Masato,Okuno, Hiroaki
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p. 823 - 824
(2007/10/03)
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- Stereoselective synthesis of (4S,5R,6S)-4-(5,6-epoxy-6-phenyl)-γ-lactone
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A short (7 steps) and efficient (45% overall yield) synthesis of (4S,5R,6S)-4-(5,6-epoxy-6-phenyl)-γ-lactone, a versatile intermediate toward possible HIV-1 protease inhibitors, is described. Two examples of trans-α- benzylation of the lactonic ring followed by a regioselective opening of the epoxide (with thiopropanamide) as well as an opening of the lactone ring with L-valine (2-methoxy-ethyl)-amide are also given.
- Solladie-Cavallo, Arlette,Roche, Didier,Bold, Guido,Acemoglu, Figan,Tintelnot-Blomley, Marina,Fischer, Jean,De Cian, Andre
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p. 1797 - 1810
(2007/10/03)
-
- Scope and Mechanism of Deprotection of Carboxylic Esters by Bis(tributyltin) Oxide
-
Methyl and ethyl esters of aliphatic and aromatic carboxylic acids as well as benzyl carboxylates, thiol esters and double esters such as (pivaloyloxy)methyl carboxylates have been successfully cleaved with bis(tributyltin) oxide to give the free carboxylic acids in good yields.The reaction is carried out in aprotic solvents under essentially neutral conditions and thus this method can serve as an ideal procedure for the cleavages of esters with other functional groups and/or protecting groups acid and/or base sensitive.We demonstrated that the reaction displays a high level of chemoselectivity between methyl and ethyl esters versus tert-butyl esters and γ-lactones.Bis(tributyltin) oxide is also a highly efficient reagent for the cleavage of acetates of primary and secondary alcohols and phenols.The limitations we found in the use of this reagent include the lack of cleavage of esters sterically hindered around the carboxyl carbon and the carbinol group (i.e., esters of tertiary alcohols) and in carboxylic esters that contain a fluoroalkyl substituent.A resonable mechanistic explanation is discussed to account for the reaction pathway of the acyloxygen cleavage of (-)-(1R)-menthyl acetate.
- Salomon, Claudio J.,Mata, Ernesto G.,Mascaretti, Oreste A.
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p. 7259 - 7266
(2007/10/02)
-
- Catalytic, Asymmetric Synthesis of the Carbacephem Framework
-
A catalytic, asymmetric synthesis of the carbacephem β-lactam framework is reported.The initial asymmetric center was established by catalytic hydrogenation of β-keto ester 12 with (S)-Ru-BINAP.The β-lactam ring was prepared using the hydroxamate approach (14 -> 15).The nitrogen substituent at C7 was introduced by the nucleophile transfer reaction (15 -> 17), and the six-membered ring of the carbacephem was prepared by a directed Dieckmann condensation (24 -> 25).
- Guzzo, Peter R.,Miller, Marvin J.
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p. 4862 - 4867
(2007/10/02)
-
- Radiolabeled proteins for diagnostic or therapeutic use
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Chelating compounds of specified N2 S2 N3 S derived structure are useful for radiolabeling targeting molecules such as antibodies. Cleavable ester orthioester linkers connect the radionuclide metal chelates to the antibodies. The radiolabeled antibodies have improved biodistribution properties, including reduced localization within the intestines and kidneys.
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- Radiolabeled proteins for diagnostic or therapeutic use
-
Chelating compounds of specified structure are useful for radiolabeling targeting molecules such as antibodies. Cleavable linkers connect the radionuclide metal chelates to the antibodies. The radiolabeled antibodies have improved biodistribution properties, including reduced localization within the intestines and kidneys.
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- Bis (tributyltin) oxide. A mild, neutral and selective reagent for cleavage of esters. Scope and limitation of the reaction
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Bis(tributyltin)oxide acts as a mild, neutral and chemoselective ester cleavage reagent for a variety of carboxylic esters with good to excellent yields. The acyl-oxygen cleavage mechanism of (-)-(1R) menthyl acetate is discussed.
- Salomon, Claudio J.,Mata, Ernesto G.,Mascaretti, Oreste A.
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p. 4239 - 4242
(2007/10/02)
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- Novel amino acid derivatives possessing renin-inhibitory activities
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An amino acid derivative of the general formula: wherein, R1? is a lower alkyl group and R11 is (wherein R111 is a lower alkyl group and n is an integer of 1 to 5) or a lower alkyl group which may be substituted by hydroxy group or methoxyethoxymethoxy group, or R1? and R11 are combinedly together with the adjacent nitrogen atom; R12 is a hydrogen atom, CnH2n+ 1-O-CO-(n is as defined above) or R13 is a lower alkyl group which may be substituted by substituent(s) selected from HOOC-(H?C)n-O-, R12-NH-(n and R12 are as defined above) and pyridyl group; X is-CH?-,-O-or-NH-and Y is-O-or-NH-; wherein (wherein Z is-O-,-S-,-S(O)-,-S(O)?-,-CH?-,-CH(OH)-,---,-NH-or and a and b are independently an integer of 1 to 4 and the total of a and b is not more than 5) ; R2 is an aralkyl group which may be substituted by lower alkyl group(s); R3 is a hydrogen atom or a lower alkyl group; R? is a lower alkyl group; and A is hydroxy group and B is a hydrogen atom, or A and B are carbonyl group combinedly together with the adjacent carbon atom, a pharmaceutically acceptable acid addition salt or an ester thereof is described. The compounds of the invention possess inhibitory activities against renin and are useful as an antihypertensive agent.
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- REMOTE SUBSTITUENT EFFECTS IN MICROBIAL REDUCTIONS OF 3-KETOGLUTARATE AND 3-KETOADIPATE ESTERS
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The enantioselectivity of yeast mediated reductions of prochiral 3-ketoglutarate and 3-ketoadipate esters to the corresponding 3-hydroxyesters can be influenced by simple differences in the ester groups.
- Brooks, Dee W.,Lee, Nola Castro de,Peevey, Richard
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p. 4623 - 4626
(2007/10/02)
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