376641-48-4Relevant academic research and scientific papers
Solvent role in the lipase-catalysed esterification of cinnamic acid and derivatives. Optimisation of the biotransformation conditions
Suárez-Escobedo, Laura,Gotor-Fernández, Vicente
, (2021/02/05)
The esterification of cinnamic acid has been deeply investigated using ethanol as nucleophile and Candida antarctica lipase type B (CAL-B) as suitable biocatalyst. Special attention has been paid to the role that the solvent plays in the production of ethyl cinnamate. Therefore, volatile organic solvents and deep eutectic mixtures were employed in order to find optimal reaction conditions. Once that hexane was selected as the solvent of choice, other parameters that affect the enzyme activity were investigated in order to produce ethyl cinnamate with excellent yield. The CAL-B loading, nucleophile equivalents, temperature and reaction time have been identified as key parameters in the enzyme efficiency, and the potential of lipase-catalysed esterification has been finally exploited to produce a series of ethyl esters with different pattern substitutions on the aromatic ring.
Enantiodivergent One-Pot Synthesis of Axially Chiral Biaryls Using Organocatalyst-Mediated Enantioselective Domino Reaction and Central-to-Axial Chirality Conversion
Hayashi, Yujiro,Koshino, Seitaro,Kwon, Eunsang,Monde, Kenji,Taniguchi, Tohru
supporting information, p. 15786 - 15794 (2021/10/14)
Enantiodivergent one-pot synthesis of biaryls was developed using a catalytic amount of a single chiral source. A domino organocatalyst-mediated enantioselective Michael reaction and aldol condensation provided centrally chiral dihydronaphthalenes with excellent enantioselectivity, from which an enantiodivergent chirality conversion from central-to-axial chirality was achieved. Both enantiomers of biaryls were obtained with excellent enantioselectivity. All transformations can be conducted in a single reaction vessel. A plausible reaction mechanism for the enantiodivergence is proposed.
N,N,N′,N′-Tetramethylenediamine dioxide (TMEDAO2) facilitates atom economical/open atmosphere Ley-Griffith (TPAP) tandem oxidation-Wittig reactions
Read, Christopher D. G.,Moore, Peter W.,Williams, Craig M.
, p. 4537 - 4540 (2015/09/15)
N,N,N′,N′-Tetramethylethylenediamine dioxide (TMEDAO2) was explored as a more atom economical co-oxidant for the Ley-Griffith oxidation of alcohols to aldehydes. TMEDAO2 was found to selectivity oxidise benzylic and allylic alcohols in comparable yields to that of the standard Ley-Griffith co-oxidant (NMO). Importantly TMEDAO2 facilitated tandem Ley-Griffith-Wittig reactions with stabilised ylides, in good to excellent yields, without the requirement of anhydrous conditions.
A Simple and Efficient Access to Naphtho[b]furans by Claisen Rearrangement/Cyclization of Bromonaphthyl 3-Phenylallyl Ethers
Wang, Wei,Huang, Jin,Zhou, Rong,Jiang, Zhi-Jie,Fu, Hai-Yan,Zheng, Xue-Li,Chen, Hua,Li, Rui-Xiang
supporting information, p. 2442 - 2446 (2015/08/18)
A transition-metal-free Claisen rearrangement/cyclization reaction was developed for the synthesis of naphthofuran derivatives from bromonaphthyl 3-phenylallyl ethers. The nature of the base employed in this reaction plays an important role in determining the ratio for the formation of naphthofuran and naphthol products. By using K2CO3 as base and DMF as solvent, we have synthesized a variety of functionalized naphthofurans in good to high yields (49-92 %) and with satisfactory selectivities.
Pyridine ligands as promoters in PdII/0-catalyzed C-H olefination reactions
Kubota, Asako,Emmert, Marion H.,Sanford, Melanie S.
supporting information; experimental part, p. 1760 - 1763 (2012/05/20)
Commercially available pyridine ligands can significantly enhance the rate, yield, substrate scope, and site selectivity of arene C-H olefination (Fujiwara-Moritani) reactions. The use of a 1:1 ratio of Pd/pyridine proved critical to maximize reaction rates and yields.
Synthesis of methoxylated goniothalamin, aza-goniothalamin and γ-pyrones and their in vitro evaluation against human cancer cells
Barcelos, Rosimeire Coura,Pastre, Julio Cezar,Caixeta, Vanessa,Vendramini-Costa, Débora Barbosa,De Carvalho, Jo?o Ernesto,Pilli, Ronaldo Aloise
experimental part, p. 3635 - 3651 (2012/07/27)
The present work describes the preparation of three novel series of compounds based on the structure of goniothalamin, a natural styryl lactone which has been found to display cytotoxic and antiproliferative activities against a variety of cancer cell lines. A focused library of 29 novel goniothalamin analogues was prepared and evaluated against seven human cancer cell lines. While the γ-pyrones and the aza-goniothalamin analogues were less potent than the lead compound, 2,4-dimethoxy analogue 88 has shown to be more potent in vitro than goniothalamin against all cancer cell lines evaluated. Furthermore, it was more potent than doxorubicin against NCI-ADR/RES, OVCAR-03 and HT-29 while being less toxic to human keratinocytes (HaCat). The 3,5-dimethoxy analogue 90 and 2,4,5-trimethoxy analogue 92 also displayed promising antiproliferative activity when compared to goniothalamin (1). These results provide new elements for the design and synthesis of novel representatives of this family of natural compounds.
Synthesis of 1,3,5-trisubstituted pyrazolines via Zn(ii)-catalyzed double hydroamination of enynes with aryl hydrazines
Patil, Nitin T.,Singh, Vipender
supporting information; experimental part, p. 11116 - 11118 (2011/11/29)
An efficient Zn(ii)-catalyzed intermolecular double hydroamination of 1,3-enynes with aryl hydrazines, for the synthesis of pyrazolines, has been discussed.
Tyrosine phosphatase inhibitors
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, (2008/06/13)
A compound of the formula (I): wherein X1 and X2 are the same or different and each is a bond or a spacer having 1 to 20 atom(s) in the main chain; one of R1 and R2 is a cycle group having substituent(s) selected from 1) an optionally substituted carboxy-C1-6 alkoxy group and 2) an optionally substituted carboxy-C1-6 aliphatic hydrocarbon group, wherein the cycle group optionally has additional substituent(s), and the other is an optionally substituted cycle group or a hydrogen atom; and R3, R4 and R5 are the same or different and each is a hydrogen atom or a substituent, or R4 may link together with R3 or R5 to form an optionally substituted ring; provided that when R3 is a hydrogen atom, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-cyclohexylphenyl; when R3 is 4-methoxyphenyl, R4 is a hydrogen atom and R5 is methyl, X2—R2 is not 4-methoxyphenyl; and when R1 or R2 is a hydrogen atom, the adjacent X1 or X2 is not a C1-7 alkylene; or a salt thereof exhibits a protein tyrosine phosphatase inhibitory action and is useful as a prophylactic or therapeutic agent for diabetes or the like.
A general model for selectivity in olefin cross metathesis
Chatterjee, Arnab K.,Choi, Tae-Lim,Sanders, Daniel P.,Grubbs, Robert H.
, p. 11360 - 11370 (2007/10/03)
In recent years, olefin cross metathesis (CM) has emerged as a powerful and convenient synthetic technique in organic chemistry; however, as a general synthetic method, CM has been limited by the lack of predictability in product selectivity and stereoselectivity. Investigations into olefin cross metathesis with several classes of olefins, including substituted and functionalized styrenes, secondary allylic alcohols, tertiary allylic alcohols, and olefins with α-quaternary centers, have led to a general model useful for the prediction of product selectivity and stereoselectivity in cross metathesis. As a general ranking of olefin reactivity in CM, olefins can be categorized by their relative abilities to undergo homodimerization via cross metathesis and the susceptibility of their homodimers toward secondary metathesis reactions. When an olefin of high reactivity is reacted with an olefin of lower reactivity (sterically bulky, electron-deficient, etc.), selective cross metathesis can be achieved using feedstock stoichiometries as low as 1:1. By employing a metathesis catalyst with the appropriate activity, selective cross metathesis reactions can be achieved with a wide variety of electron-rich, electron-deficient, and sterically bulky olefins. Application of this model has allowed for the prediction and development of selective cross metathesis reactions, culminating in unprecedented three-component intermolecular cross metathesis reactions.
Isoxazole compounds useful for the prophylaxis or treatment of nervous diseases
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, (2008/06/13)
Isoxazole compounds having the following general formula: STR1 wherein R1 represents an optionally substituted aryl group or aromatic heterocyclic group; R2 represents a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an alkoxy group, a cyano group, a carboxyl group, an alkanoyl group, an alkoxycarbonyl group or an optionally substituted carbamoyl group; R3 represents an optionally substituted amino group or a saturated heterocyclic group; X represents an oxygen atom or a sulfur atom; and n is an integer of from 2 to 6. These compounds have excellent monoamine oxidase inhibitory activity and are useful as a therapeutic agent or a preventive agent against nervous diseases such as depression.
