20716-25-0Relevant academic research and scientific papers
Biocatalytic reduction of α,β-unsaturated carboxylic acids to allylic alcohols
Aleku, Godwin A.,Leys, David,Roberts, George W.
, p. 3927 - 3939 (2020/07/09)
We have developed robust in vivo and in vitro biocatalytic systems that enable reduction of α,β-unsaturated carboxylic acids to allylic alcohols and their saturated analogues. These compounds are prevalent scaffolds in many industrial chemicals and pharmaceuticals. A substrate profiling study of a carboxylic acid reductase (CAR) investigating unexplored substrate space, such as benzo-fused (hetero)aromatic carboxylic acids and α,β-unsaturated carboxylic acids, revealed broad substrate tolerance and provided information on the reactivity patterns of these substrates. E. coli cells expressing a heterologous CAR were employed as a multi-step hydrogenation catalyst to convert a variety of α,β-unsaturated carboxylic acids to the corresponding saturated primary alcohols, affording up to >99percent conversion. This was supported by the broad substrate scope of E. coli endogenous alcohol dehydrogenase (ADH), as well as the unexpected CC bond reducing activity of E. coli cells. In addition, a broad range of benzofused (hetero)aromatic carboxylic acids were converted to the corresponding primary alcohols by the recombinant E. coli cells. An alternative one-pot in vitro two-enzyme system, consisting of CAR and glucose dehydrogenase (GDH), demonstrates promiscuous carbonyl reductase activity of GDH towards a wide range of unsaturated aldehydes. Hence, coupling CAR with a GDH-driven NADP(H) recycling system provides access to a variety of (hetero)aromatic primary alcohols and allylic alcohols from the parent carboxylates, in up to >99percent conversion. To demonstrate the applicability of these systems in preparative synthesis, we performed 100 mg scale biotransformations for the preparation of indole-3-aldehyde and 3-(naphthalen-1-yl)propan-1-ol using the whole-cell system, and cinnamyl alcohol using the in vitro system, affording up to 85percent isolated yield.
Catalytic Transfer Hydrogenation Using Biomass as Hydrogen Source
Antonchick, Andrey P.,Manna, Srimanta
, p. 3094 - 3098 (2018/09/14)
We developed an operationally simple method for the direct use of biomass-derived chemical entities in a fundamentally important process, such as hydrogenation. Various carbohydrates, starch, and lignin were used for stereoselective hydrogenation. Employing a transition metal catalyst and a novel catalytic system, the reduction of alkynes, alkenes, and carbonyl groups with high yields was demonstrated. The regioselective hydrogenation to access different stereoisomers was established by simple variations in the reaction conditions. This work is based on an unprecedented catalytic system and represents a straightforward application of biomass as a reducing reagent in chemical reactions.
Metal-Organic Capsules with NADH Mimics as Switchable Selectivity Regulators for Photocatalytic Transfer Hydrogenation
Wei, Jianwei,Zhao, Liang,He, Cheng,Zheng, Sijia,Reek, Joost N. H.,Duan, Chunying
, p. 12707 - 12716 (2019/09/04)
Switchable selective hydrogenation among the groups in multifunctional compounds is challenging because selective hydrogenation is of great interest in the synthesis of fine chemicals and pharmaceuticals as a result of the importance of key intermediates. Herein, we report a new approach to highly selectively (>99%) reducing C=X (X = O, N) over the thermodynamically more favorable nitro groups locating the substrate in a metal-organic capsule containing NADH active sites. Within the capsule, the NADH active sites reduce the double bonds via a typical 2e- hydride transfer hydrogenation, and the formed excited-state NAD+ mimics oxidize the reductant via two consecutive 1e- processes to regenerate the NADH active sites under illumination. Outside the capsule, nitro groups are highly selectively reduced through a typical 1e- hydrogenation. By combining photoinduced 1e- transfer regeneration outside the cage, both 1e- and 2e- hydrogenation can be switched controllably by varying the concentrations of the substrates and the redox potential of electron donors. This promising alternative approach, which could proceed under mild reaction conditions and use easy-to-handle hydrogen donors with enhanced high selectivity toward different groups, is based on the localization and differentiation of the 2e- and 1e- hydrogenation pathways inside and outside the capsules, provides a deep comprehension of photocatalytic microscopic reaction processes, and will allow the design and optimization of catalysts. We demonstrate the advantage of this method over typical hydrogenation that involves specific activation via well-modified catalytic sites and present results on the high, well-controlled, and switchable selectivity for the hydrogenation of a variety of substituted and bifunctional aldehydes, ketones, and imines.
Radiolabeled inhibitors as probes for imaging mutant IDH1 expression in gliomas: Synthesis and preliminary evaluation of labeled butyl-phenyl sulfonamide analogs
Chitneni, Satish K.,Reitman, Zachary J.,Gooden, David M.,Yan, Hai,Zalutsky, Michael R.
, p. 218 - 230 (2016/05/19)
Introduction: Malignant gliomas frequently harbor mutations in the isocitrate dehydrogenase 1 (IDH1) gene. Studies suggest that IDH mutation contributes to tumor pathogenesis through mechanisms that are mediated by the neomorphic metabolite of the mutant
Copper-catalyzed Z-selective semihydrogenation of alkynes with hydrosilane: A convenient approach to cis-alkenes
Wang, Guang-Hui,Bin, Huai-Yu,Sun, Miao,Chen, Shu-Wei,Liu, Ji-Hong,Zhong, Chong-Min
supporting information, p. 2175 - 2179 (2014/03/21)
A copper catalyst generated in situ from widely available copper salt and imidazolium salt in the presence of t-BuOK showed high efficiency for the semihydrogenation of a wide range of internal and terminal alkynes to their corresponding alkenes without obvious over-reduction. Functional groups, such as hydroxyl, nitro, halides, and amino, etc. were tolerated. The Z/E ratios of the obtained alkenes were generally >99%. Finally, semireduction of bulky alkynes also went smoothly.
4-alkyloxyimino derivatives of uridine-5′-triphosphate: Distal modification of potent agonists as a strategy for molecular probes of P2Y 2, P2Y4, and P2Y6 receptors
Jayasekara, P. Suresh,Barrett, Matthew O.,Ball, Christopher B.,Brown, Kyle A.,Hammes, Eva,Balasubramanian, Ramachandran,Harden, T. Kendall,Jacobson, Kenneth A.
, p. 3874 - 3883 (2014/05/20)
Extended N4-(3-arylpropyl)oxy derivatives of uridine-5′-triphosphate were synthesized and potently stimulated phospholipase C stimulation in astrocytoma cells expressing G protein-coupled human (h) P2Y receptors (P2YRs) activated by UTP (P2Y2/4R) or UDP (P2Y6R). The potent P2Y4R-selective N4-(3- phenylpropyl)oxy agonist was phenyl ring-substituted or replaced with terminal heterocyclic or naphthyl rings with retention of P2YR potency. This broad tolerance for steric bulk in a distal region was not observed for dinucleoside tetraphosphate agonists with both nucleobases substituted. The potent N 4-(3-(4-methoxyphenyl)-propyl)oxy analogue 19 (EC50: P2Y2R, 47 nM; P2Y4R, 23 nM) was functionalized for chain extension using click tethering of fluorophores as prosthetic groups. The BODIPY 630/650 conjugate 28 (MRS4162) exhibited EC50 values of 70, 66, and 23 nM at the hP2Y2/4/6Rs, respectively, and specifically labeled cells expressing the P2Y6R. Thus, an extended N4-(3- arylpropyl)oxy group accessed a structurally permissive region on three G q-coupled P2YRs, and potency and selectivity were modulated by distal structural changes. This freedom of substitution was utilized to design of a pan-agonist fluorescent probe of a subset of uracil nucleotide-activated hP2YRs.
Indium-catalyzed reductive bromination of carboxylic acids leading to alkyl bromides
Moriya, Toshimitsu,Yoneda, Shinichiro,Kawana, Keita,Ikeda, Reiko,Konakahara, Takeo,Sakai, Norio
supporting information, p. 4842 - 4845,4 (2020/09/16)
The combination of 1,1,3,3-tetramethyldisiloxane (TMDS) and trimethylbromosilane (Me3SiBr) with a catalytic amount of indium bromide (InBr3) undertook direct bromination of carboxylic acids, which produced the corresponding alkyl bromides in good to excellent yields. The reducing system was tolerant to several functional groups.
Synthesis of tetrahydronaphthalene lignan esters by intramolecular cyclization of ethyl p-azidophenyl-2-phenylalkanoates and evaluation of the growth inhibition of human tumor cell lines
Pinto, Orlando,Sardinha, Jo?o,Vaz, Pedro D.,Piedade, Fátima,Calhorda, Maria J.,Abramovitch, Rudolph,Nazareth, Nair,Pinto, Madalena,Nascimento, Maria S. J.,Rauter, Amélia P.
experimental part, p. 3175 - 3187 (2011/07/30)
Figure Presented. Intramolecular cyclization via nitrenium ion of 2-phenylpentanoic/2-phenylbutanoic acid esters with a terminal p-azidophenyl group gives direct access to tetrahydronaphthalene lignan esters. The p-azidophenyl-substituted butanoate led to
Development of molecular sieves-supported palladium catalyst and chemoselective hydrogenation of unsaturated bonds in the presence of nitro groups
Maegawa, Tomohiro,Takahashi, Tohru,Yoshimura, Masatoshi,Suzuka, Hiroyasu,Monguchi, Yasunari,Sajiki, Hironao
supporting information; experimental part, p. 2091 - 2095 (2009/12/26)
The chemoselective hydrogenation of unsaturated bonds and azide functionalities is achieved in the presence of nitro groups by a heterogeneous palladium catalyst supported on molecular sieves (MS3A). The present method shows a widerange of applicability with regard to substrates and the catalyst can be easily prepared and reused at least three times without any loss of activity.
MACROLIDE COMPOUNDS AND METHODS OF MAKING AND USING THE SAME
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Page/Page column 118-119, (2008/12/07)
The present invention provides amide containing macrocyclic compounds useful as therapeutic agents. More particularly, these compounds are useful as anti-infective, anti-proliferative, anti-inflammatory, and prokinetic agents.
