cas 10203-58-4, Diethyl isobutylmalonate | Articles data

Articles about 10203-58-4Total 22 be found

Article title
Article abstract
Author
Journal number and time
Download

FRUSTRATED LEWIS PAIR-IMPREGNATED POROUS MATERIALS AND USES THEREOF
Described herein are compositions composed of frustrated Lewis pairs impregnated in porous materials such as, for example, metal-organic frameworks, and their uses thereof. These compositions may allow new applications of frustrated Lewis pairs in catalysis by sequestering and protecting the frustrated Lewis pair within the nanospace of the porous material. Also provided are methods of hydrogenating an organic compound having at least one unsaturated functional group comprising using the compositions described herein.
-
Page/Page column 73; 80-81

(2021/01/23)

Metal-Organic Framework Anchored with a Lewis Pair as a New Paradigm for Catalysis
Lewis pair (LP) chemistry has shown broad applications in the catalysis field. However, one significant challenge has been recognized as the instability for most homogeneous LP catalysts upon recycling, thus inevitably leading to dramatic loss in catalytic activity. Additionally, current heterogeneous LP catalysts suffer from low surface area, which largely limits their catalytic efficiency, thereby restricting their potential applications. In this work, we report the successful introduction of LPs, classical and frustrated, into a metal-organic framework (MOF) that features high surface and ordered pore structure via a stepwise anchoring strategy. Not only can the LP be stabilized by the strong coordination interaction between the LP and MOF, but the resultant MOF-LP also demonstrates excellent catalysis performance with interesting size and steric selectivity. Given the broad applicability of LPs, our work therefore paves a way for advancing MOF-LP as a new paradigm for catalysis. Lewis pairs (LPs), classical and frustrated, are excellent prospects in catalysis, organic syntheses, biology, and material sciences. However, the instability of most LP catalysts leads to a dramatic loss in activities, thereby largely restricting their industrial applications. As robust porous materials, metal-organic frameworks (MOFs) offer a platform to stabilize homogeneous catalysts. Here, we show a strategy that grafts the LP catalyst on the MOF to minimize loss of LPs during catalysis and recycling. Our work reveals the enormous potential of MOFs as an appealing paradigm for the construction of efficient heterogeneous catalysts with interesting steric and size selectivity worthy of exploration. In addition, the strategies for anchoring a LP into a MOF as contributed herein can be readily applied for the task-specific design of functional catalysis materials for various applications. Lewis pairs (LPs), classical and frustrated, have been successfully introduced into and stabilized in a metal-organic framework (MOF). Benefiting from the robust framework and tunable porous structure of MOFs, the resultant MOF-LP demonstrates not only great recyclability but also excellent performance in the catalytic reduction of imines and hydrogenation of alkenes. The combination of LP and MOF therefore lays a foundation for developing a MOF-LP as a new paradigm for catalysis, particularly heterogeneous catalysis.
Niu, Zheng,Bhagya Gunatilleke, Wilarachchige D.C.,Sun, Qi,Lan, Pui Ching,Perman, Jason,Ma, Jian-Gong,Cheng, Yuchuan,Aguila, Briana,Ma, Shengqian
p. 2587 - 2599
(2018/12/02)

Functional examination of novel kisspeptin phosphinic peptides
Kisspeptins acting on their cognate G protein-coupled receptor, kisspeptin receptor, play important roles in the suppression of cancer cell metastasis and regulation of the reproductive system, and therefore are important for therapeutic intervention. All native functional human kisspeptins (kisspeptin-54, kisspsptin-14 and kisspeptin-13) share the 10 amino acids of kisspeptin-10 at their C-terminus (45-54). However, they are inactivated rapidly by matrix metalloproteinases (MMPs) through the cleavage of the peptide bond between glycine 51 and leucine52, which limits their clinical applications. Development of MMP-resistant analogues of kisspeptins may provide better therapeutic outputs. In the present study, two kisspeptin phosphinic peptides were designed and synthesized, and their ability to induce phosphorylation of ERK1/2 through kisspeptin receptor and their inhibition on MMP-2 and MMP-9 whose activity correlates with cancer metastasis were assessed. The results showed that one analogue, phosphinic kisspeptin R isomer (PKPR), exhibited kisspeptin receptor-agonistic activity and also inhibitory activity on MMP-2, indicating that PKPR may serve as a lead for the further development of kisspeptin analogues for therapeutic purpose.
Zhang, Xiaoyang,Matziari, Magdalini,Xie, Yixin,Fernig, David,Rong, Rong,Meng, Jia,Lu, Zhi-Liang
(2018/04/12)

Palladium-Catalyzed Atom-Transfer Radical Cyclization at Remote Unactivated C(sp3)?H Sites: Hydrogen-Atom Transfer of Hybrid Vinyl Palladium Radical Intermediates
A novel mild, visible-light-induced palladium-catalyzed hydrogen atom translocation/atom-transfer radical cyclization (HAT/ATRC) cascade has been developed. This protocol involves a 1,5-HAT process of previously unknown hybrid vinyl palladium radical intermediates, thus leading to iodomethyl carbo- and heterocyclic structures.
Ratushnyy, Maxim,Parasram, Marvin,Wang, Yang,Gevorgyan, Vladimir
supporting information
p. 2712 - 2715
(2018/03/02)

A amide alkaloid fully synthetic method
The invention discloses a total synthesis method of amides alkaloid, and belongs to the technical field of the chemistry of natural products. The total synthesis method comprises the following steps: carrying out the synthesis by adopting malonate and 2-bromopropane or 2-bromopropane derivative as raw materials, thereby obtaining isopropyl malonate; (2) carrying out the synthesis by adopting 2-aminopyrrolidine as a raw material, thereby obtaining mid-body 2-amino tetralin pyrrolidine; and (3) synthesizing amides alkaloid 3-isopropyl-nafoxidine[1,2-alpha]pyrimidine-2,4(1H,3H)-diketone and a derivative by adopting the isopropyl malonate and the 2-2-amino tetralin pyrrolidine as a raw material. By adopting the total synthesis method, the defect that the extraction separation process in the natural product is complicated and the yield is low can be overcome, and the demand of perople for further researching the natural product can be satisfied; moreover, the synthesis method is simple in route, raw materials are cheap and easy to obtain, and the yield is relatively high.
-
Paragraph 0080; 0081

(2017/08/25)

Creation through immobilization: A new family of high performance heterogeneous bifunctional iminophosphorane (BIMP) superbase organocatalysts
An immobilized chiral bifunctional iminophosphorane superbase organocatalyst has been developed and applied in a range of challenging enantioselective reactions. A unique feature of this novel catalytic system is that the final step creation of the iminophosphorane occurs at the point of immobilization. The utility of the immobilized catalyst system was demonstrated in the nitro-Mannich reaction of ketimines as well as the conjugate addition of high pKa 1,3-dicarbonyl pro-nucleophiles to nitrostyrene. Catalyst recycling was also demonstrated.
Goldys, Anna M.,Nez, Marta G.,Dixon, Darren J.
supporting information
p. 6294 - 6297
(2015/02/05)

Metal-free hydrogenation of electron-poor allenes and alkenes
The poorer, the better: A metal-free catalytic procedure for the reduction of electron-poor allenes and alkenes has been developed. The method employs a frustrated Lewis pair based catalyst. 1,4-Diazabicyclo[2.2.2]octane (DABCO)/B(C6F5)3 was shown to be the best combination in optimization studies. Copyright
Ines, Blanca,Palomas, David,Holle, Sigrid,Steinberg, Sebastian,Nicasio, Juan A.,Alcarazo, Manuel
supporting information
p. 12367 - 12369
(2013/02/22)

Malonic acid based matrix metalloproteinase inhibitors
There is described the use of a compound represented by general formulae (I), (II) or (III), for the inhibition of matrix metalloproteinases (MMP), wherein X1 is oxygen or sulfur, R1 is OH, SH, CH2OH, CH2SH or NHOH, R2 is a residue of 2 to 10 hydrocarbon backbone atoms, which binds to the amino acid 161 of HNC, said residue being saturated or unsaturated, linear or branched, and contains preferably homocyclic or heterocyclic structures, X2 is oxygen or sulfur and binds as hydrogen acceptor on amino acid 160 of HNC, Y is a residue which binds to the S1′ pocket of HNC and consists of at least 4 backbone atoms Z1-Z2-Z3-Z4-R3, and R3 is n-propyl, isopropyl, isobutyl or a residue with at least 4 backbone atoms, which is not larger than a tricyclic ring system. These compounds bind to MMPs in a manner different from the mode of binding of the inhibitors of the state of the art.
-
(2008/06/13)

Mixed Dialkylaluminum Chlorides and Mixed Trimethylorganoaluminates in Chemoselective 1,4 Addition Reactions to Alkylidene Malonic Acid Diethyl Ester
Mixed alkyl-methyl- and aryl-methylorganoaluminum chlorides 6 were formed by reaction of methylaluminum dichloride with organolithium or Grignard compounds and used for chemoselective 1,4 addition of higher alkyl, aryl, alkenyl and alkinyl groups to alkylidine malonic esters 1 and 2. As an alternative, mixed trimethylorganoaluminates 7 can also be applied for these Michael addition reactions. For conjugate addition of alkenyl groups to alkylidene malonates 1 and 2, alkenyl diisopropylalanes 10 obtained from alkynes and diisopropylaluminum hydride proved the most efficient reagents. Using these novel mixed organoaluminum compounds, β-branched malonic (carboxylic) acid derivatives 3c, 8, 9 and 11 were obtained in good yields. The method offers a general access to β-branched carboxylic derivatives of quite diverse structure not dependent on the commercial availability of the organoluminum chlorides.
Maas, Steffen,Kunz, Horst
p. 396 - 403
(2007/10/03)

Utilization of the 1,2,5-thiadiazolidin-3-one 1,1 dioxide scaffold in the design of potent inhibitors of serine proteases: SAR studies using carboxylates
A series of carboxylate derivatives based on the 1,2,5-thiadiazolidin-3- one 1,1 dioxide and isothiazolidin-3-one 1,1 dioxide scaffolds has been synthesized and the inhibitory profile of these compounds toward human leukocyte elastase (HLE), cathepsin G (Cat G) and proteinase 3 (PR 3) was then determined. Most of the compounds were found to be potent, time- dependent inhibitors of elastase, with some of the compounds exhibiting k(inact)/K(I) values as high as 4,928,300 M-1 s-1. The inhibitory potency of carboxylate derivatives based on the 1,2,5-thiadiazolidin-3-one 1,1 dioxide platform was found to be influenced by both the pK(a) and the inherent structure of the leaving group. Proper selection of the primary specificity group (R1) was found to lead to selective inhibition of HLE over Cat G, however, those compounds that inhibited HLE also inhibited PR 3, albeit less efficiently. The predictable mode of binding of these compounds suggests that, among closely-related serine proteases, highly selective inhibitors of a particular serine protease can be fashioned by exploiting subtle differences in their S' subsites. This study has also demonstrated that the degradative action of elastase on elastin can be abrogated in the presence of inhibitor 17. (C) 2000 Elsevier Science Ltd.
Kuang, Rongze,Epp, Jeffrey B.,Ruan, Sumei,Chong, Lee S.,Venkataraman, Radhika,Tu, Juan,He, Shu,Truong, Tien M.,Groutas, William C.
p. 1005 - 1016
(2007/10/03)

Conjugate addition of dialkylaluminum chlorides to alkylidenemalonic acid derivatives
Complete regioselectivity is achieved in conjugate addition reactions of dialkylaluminum chlorides with alkylidenemalonic esters, alkylidenecyanoacetates, and alkylidenemalonodinitrile to give β-branched carboxylic acid derivatives. Sterically demanding products containing quaternary carbon atoms are obtained in good yields. In the case of diethylaluminum chloride, accompanying reductions of the substrates can be suppressed by application of boron trifluoride as an assisting Lewis acid.
Maas, Steffen,Stamm, Armin,Kunz, Horst
p. 1792 - 1798
(2007/10/03)

PHOSPHINIC ACID DERIVATIVES WITH METALLOPEPTIDASE INHIBITORY ACTIVITY
Compounds of formula (I), STR1 wherein R is a biphenyl group optionally substituted, by one or more substituents, the same or different selected among halogen atoms, hydroxy groups, alkoxy, alkyl thioalkyl or alkoxycarbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety, C 1-C 3 alkyl groups containing one or more fluorine atoms, carboxy groups, nitro groups, amino or aminocarbonyl groups, acylamino groups, aminosulphonyl groups, momo-or di-alkylamino groups having from 1 to 6 carbon atoms in the alkyl moiety, mono-or di-alkylamino-carbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety; R 1 is a hydrogen atom, a straight or branched C 1-C 6 alkyl group or an arylalkyl group having from 1 to 6 carbon atoms in the alkyl moiety wherein the aryl is a phenyl, a biphenyl, a napthyl or a 5 or 6 membered aromatic heterocycle with one or two heteroatoms selected among nitrogen, oxygen and sulphur, optionally substituted with one or more substituents, the same or different, selected among halogen atoms, hydroxy groups, alkoxy, alkyl, thioalkyl or alkoxycarbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety, C 1-C 3 alkyl groups containing one or more fluorine atoms, carboxy groups, nitro groups, amino or aminocarbonyl groups, acylamino groups, aminosulphonyl groups, mono-or di-alkylamino groups having from 1 to 6 carbon atoms in the alkyl moiety, mono-or di-alkylaminocarbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety; R 2 is a straight or branched C. sub.1-C 6 alkyl group, optionally containing one or more fluorine atoms or one or more--NH--groups, an arylalkyl, an arylcarbonylaminoalkyl, an arylalkylcarbonylaminoalkyl or an arylaminocarbonylalkyl group having from 1 to 6 carbon atoms and optionally one or more--NH--groups in the alkyl moiety, the aryl being optionally substituted by one or more substituents, the same or different, selected among halogen atoms, hydroxy groups, alkoxy, alkyl, thioalkyl or alkoxycarbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety, C 1-C. sub.3 alkyl groups containing one or more fluorine atoms, carboxy groups, nitro groups, amino or aminocarbonyl groups, acylamino groups, aminosulphonyl groups, mono-or di-alkylamino groups having from 1 to 6 carbon atoms in the alkyl moiety, mono-or di-alkylaminocarbonyl groups having from 1 to 6 carbon atoms in the alkyl moiety; m is 0 or 1; X is a hydrogen or fluorine atom; the carbon atom marked with an asterisk is an asymmetric carbon atom; and their pharmaceutically acceptable salts, are described. The compounds of formula (I) are endowed with a mixed ACE-inhibitory and NEP-inhibitory activity and are useful in the treatment of cardiovascular diseases.
-
(2008/06/13)

An Efficient Synthesis of Some 6-Substituted 4,8-Diaza-3,3,9,9-tetramethylundeca-2,10-dione Dioximes (Propylene Amine Oximes, PnAOs): Ligands for 99mTc Complexes Used in Structure Distribution Relationship (SDR) Studies
Technetium complexes of the ligand PnAO are of interest as commercial radiopharmaceuticals.In general, PnAOs are synthesized by alkylation of a propylenediamine derivative with 3-chloro-3-methyl-2-nitrosobutane (2).This alkylation reaction proved to be low yielding.With modestly bulky substituents at the 2-position of 1,3-diaminopropane, little or none of the required PnAO was obtained.As a result, an alternative approach of the synthesis of PnAO was developed.This method involved the alkylation of the propylenediamine with 3-bromo-3-methylbutan-2-one (18) followed by oximation of the resulting diamine-diketone (19).By this method, PnAOs were prepared in good yield, even with bulky C-2 substituents.Fourteen PnAO derivatives were prepareed by this method.We also describe the syntheses of several new propylenediamine dervatives.
Nanjappan, Palaniappa,Raju, Natarajan,Ramalingam, Kondareddiar,Nowotnik, David P.
p. 8617 - 8632
(2007/10/02)

Phosphoramidate peptide inhibitors of human skin fibroblast collagenase
An extensive series of N-(monoethylphosphoryl)peptides was synthesized and their inhibition of purified human skin fibroblast collagenase examined. At the cleavage site S1 all reported compounds have the (EtO)(OK)P(O) group and the peptide side chain extended toward the C-terminal end (up to P5') of the substrate sequence. These phosphoramidates with a tetrahedrally hybridized phosphorus atom are thought to be transition state analogue inhibitors. They exhibited fair inhibitory potency against this vertebrate collagenase having K(i) values in the micromolar range. The most potent of these, (EtO)(OK)P(O)-Ile-TrpNHCH3 (68), inhibits with a K(i) value of 1.5 μM and is nearly 100 times stronger than (EtO)(OK)P(O)-Ile-Ala-GlyOK (51) (K(i) of 140 μM), which has the sequence matching that of the α1(I) chain of collagen in P1', P2', P3' after the cleavage site. Several compounds were prepared in an attempt to identify the nature of the S2', S3', and S4' binding sites. Alanine at the P2' position was replaced by leucine, phenylalanine, tryptophan, or tyrosine derivatives, resulting in K(i) values in a significantly lower range, 1.0-40 μM, compared to 51. No upper size limitation or specificity has been found at this position, yet similar replacements at the P3' position, which is occupied naturally by a glycine residue, gave weaker inhibitors: (EtO)(OK)P(O)-Ile-Tyr(OBzl)-PheOK (57) had a K(i) of 120 μM. Hexapeptide derivatives had weaker activities in the 270 μM-2 mM range. All inhibitors were evaluated by using the synthetic thio peptolide spectrophotometric assay.
Kortylewicz,Galardy
p. 263 - 273
(2007/10/02)

EtAlCl2-Catalyzed Reactions of Alkenes with Electrophillic Cyclopropanes. A New Cyclopentane Annelation Reaction
Treatment of 1,1-di-, tri-, and tetrasubstituted alkenes with diethyl cyclopropane-1,1-dicarboxylate (1) and 2 equiv of EtAlCl2 gives zwitterions which collapse to cyclopentanedicarboxylates in good to excellent yield.This reaction provides a general procedure for the annelation of cyclopentanes to alkenes.The intermediate zwitterions undergo the 1,2-hydride and -methyl shifts characteristic of carbocations, although these side reactions are generally minor.Diethyl 2-methylcyclopropane-1,1-dicarboxylate (38) reacts similarly with alkenes at the more substituted carbon of 38 to give 3-methylcyclopentane-1,1-dicarboxylates.Diethyl 2,2-dimethylcyclopropane-1,1-dicarboxylate (46) rearranges in the presence of EtAlCl2 to diethyl isobutylidenemalonate, which reacts with alkenes and is reduced by EtAlCl2.The intramolecular Lewis acid induced addition of alkenes to cyclopropanedicarboxylate esters occurs analogously.
Beal, Richard B.,Dombroski, Mark A.,Snider, Barry B.
p. 4391 - 4399
(2007/10/02)

Synthesis and some pharmacological properties of alkyl esters of various dl-ω-phenylamino acids
-
Schulz,Sprung,Kroning
p. 310 - 313
(2007/10/02)

Inhibitors of mammalian collagenase
Mammalian collagenase is inhibited by compounds of the formula STR1 or salts thereof, wherein R is hydrogen, alkanoyl of 2 to 10 carbon atoms or arylcarbonyl;R 1 is of 3 to 8 carbon atoms, cycloalkyl of 3 to 7 carbon atoms, aryl or arylalkyl; STR2 R 4 is hydrogen, methyl, ethyl, or STR3 R 5 and R 6 are each independently selected as --OCH 3 or --OCH 2 CH 3 or are combined as --OCH 2 CH 2 O-- or --O--(CH 2)--O--;R 7 and R 8 are each independently selected as hydrogen, methyl or ethyl or are combined as --(CH 2) 4 --, --(CH 2) 5 -- or --CH 2 CH 2 --O--CH 2 CH 2 --;R 9 is hydrogen, methyl, ethyl STR4 m is an integer from 0 to 7; p is an integer from 1 to 3; AA n is an amino acid chain of from one to three amino acids; n is 1 or 1, 2 or 1, 2, 3;when p is 1, AA n is AA 1 ;when p is 2, AA n is AA 1 --AA 2 ;when p is 3, AA n is AA 1 --AA 2 --AA 3 ;AA 1 is glycine or alanine;AA 2 is glycine or alanine;AA 3 is leucine, glutamine or isoleucine.A method of reducing the adverse effects of mammalian collagenase in a mammalian host in need thereof, which comprises administering to the mammal an effective amount of a compound having the above formula is within the scope of the invention.
-
(2008/06/13)

Synthesis and some spectral characteristics of bicyclic phosphate, GABA antagonists
-
Ozoe,Eto
p. 411 - 418
(2007/10/02)

The Reactivity of Carbenes from Photolysis of Diazo-Compounds towards Carbon-Hydrogen Bonds. Effects of Structure, Temperature, and Matrix on the Insertion Selectivity
Direct and/or sensitized photolyses of diazo-acetate (1a) and -malonate (1b) in hydrocarbons and ether were investigated at various temperatures in order to learn more about the nature of the C-H insertion process and the structural factors governing positional selectivity within the matrix.Photolysis of the diazo-compounds in a rigid matrix resulted in a marked decrease in the insertion selectivity, which may be interpreted as indicating that the matrix imposes severe steric demand especially on the direct C-H insertion process of the singlet carbene.The addition of a sensitizer in matrix photolysis causes a marked increase in the selectivity in the case of (1a), as is observed in the comparable liquid-phase experiment, but it causes a decrease in the case of (1b).This is interpreted as suggesting that the excited triplet (1b) itself is involved in C-H insertion under these conditions.More extensive temperature studies show that, as the temperature decreases, the C-H insertion selectivity of :CHCO2R decreases regularly regardless of the reaction phase, whereas that of :C(CO2R)2 increases in the liquid phase but decreases in the solid phase.This difference in the temperature dependence is explained by assuming that the singlet carbene is responsible for the C-H insertion of :CHCO2R throughout the temperature range studied, while both singlet and triplet are involved in the insertion of :C(CO2R)2.
Tomioka, Hideo,Itoh, Masami,Yamakawa, Shyoji,Izawa, Yasuji
p. 603 - 609
(2007/10/02)

Structure-activity relations in 2,6,7-trioxa-1-phosphabicyclo (2,2,2) octanes and related compounds
-
Cooper,Lawston,Rickard,Inch
p. 207 - 212
(2007/10/10)

6-Acyl derivatives of aminopenicillanic acid
Compounds represented by the following formula STR1 wherein R is hydrogen, lower alkanoyloxymethyl, lower alkyl, indanyl or a radical represented by the formula STR2 wherein X may be hydrogen, halogen, hydroxy, lower alkyl, lower alkoxy or a lower alkoxy-lower alkyl group, Pharmaceutically acceptable salts and hydrates thereof. These compounds are useful as antibiotics.
-
(2008/06/13)

Mass spectrometry in structural and stereochemical problems. CCXXX. Preparation of 5α,20α and 5α,17α,20α cholestane 3β,6α diol. Electron impact induced fragmentation of steroidal Δ17(20), Δ20(21), and Δ20(22) olefins
-
Sheikh,Djerassi
p. 3545 - 3554
(2007/10/10)