25568-84-7Relevant articles and documents
Photo-oxidation of Cyclopentadiene Using Continuous Processing: Application to the Synthesis of (1 R,4 S)-4-Hydroxycyclopent-2-en-1-yl Acetate
Allais, Christophe,Herrero-Gomez, Elena,Huck, Lena,Keene, Nandell F.,Li, Bryan,Pouwer, Kees,Rioz-Martínez, Ana,Van Der Loo, Cornelis H. M.
, p. 2304 - 2310 (2020)
(1R,4S)-4-Hydroxycyclopent-2-en-1-yl acetate is a chiral small building block that was requested to advance several Pfizer programs into the clinic. Pfizer and Syncom partnered to develop a photo-oxidation process of cyclopentadiene using a flow approach followed by subsequent bis-acetylation of the meso diol and final biocatalytic desymmetrization. This continuous process was demonstrated on a 6 g·h-1 input and is amenable to larger scale. The optimization and scale-up of this sequence is described therein.
Synthesis & antitumor activity of new group 3 Metallocene complexes
Caporale, Angelamaria,Palma, Giuseppe,Mariconda, Annaluisa,Del Vecchio, Vitale,Iacopetta, Domenico,Parisi, Ortensia Ilaria,Sinicropi, Maria Stefania,Puoci, Francesco,Arra, Claudio,Longo, Pasquale,Saturnino, Carmela
, (2017)
The quest for alternative drugs with respect to the well-known cis-platin and its derivatives, which are still used in more than 50% of the treatment regimens for patients suffering from cancer, is highly needed. In this context, organometallic compounds, which are defined as metal complexes containing at least one direct covalent metal-carbon bond, have recently been found to be promising anticancer drug candidates. A series of new metallocene complexes with scandium, yttrium, and neodymium have been prepared and characterized. Some of these compounds show a very interesting anti-proliferative activity in triple negative breast cancer cell line (MDA.MB231) and the non-hormone sensitive prostate cancer cell line (DU145). Moreover, the interaction of some of them with biological membranes, evaluated using liposomes as bio-membrane mimetic model systems, seems to be relevant. The biological activity of these compounds, particularly those based on yttrium, already effective at low concentrations on both cancer cell lines, should be taken into account with regard to new therapeutic approaches in anticancer therapy.
THERMAL REACTIONS OF CYCLOBUTANEDIONES
Rubin, Mordecai B.,Harel, Yaakov
, p. 5373 - 5376 (1987)
Thermolysis of cyclobutanediones in hydrocarbon solvents shows marked dependence on structure and may involve bis-decarbonylation to olefins, monodecarbonylation with rearrangement to cyclopentenone derivatives, or rearrangement without loss of carbon monoxide.
Retro-Diels-Alder Reaction in Aqueous Solution: Toward a Better Understanding of Organic Reactivity in Water
Wijnen, Jan W.,Engberts, Jan B.F.N.
, p. 2039 - 2044 (1997)
The retro-Diels-Alder (RDA) reaction of anthracenedione 1a proceeds considerably faster in aqueous solutions than in organic solvents. Addition of organic solvents to water retards the reaction, whereas glucose induces a modest acceleration. SDS micelles induce a considerable retardation, but even at high concentrations of surfactant (complete micelle-substrate binding), the cycloreversion is not fully inhibited. Correlation with data for solvatochromic indicators strongly suggest that the origin of the water-induced acceleration involves primarily enhanced hydrogen bonding of water to the activated complex for the RDA reaction of 1a. Activation parameters support this view. A comparison of the present results with previous kinetic data for bimolecular and intramolecular Diels-Alder reactions provides insights into the contributions of hydrogen-bond and hydrophobic interactions to the aqueous accelerations of the latter two types of reactions.
Inverse electron demand Diels-Alder (iEDDA) functionalisation of macroporous poly(dicyclopentadiene) foams
Knall, Astrid-Caroline,Kovacic, Sebastijan,Hollauf, Manuel,Reishofer, David,Saf, Robert,Slugovc, Christian
, p. 7325 - 7327 (2013)
Inverse electron demand Diels-Alder reactions performed on the double bonds in open cellular macroporous poly(dicyclopentadiene) monoliths yield a high degree of functionalisation (up to 2 mmol pyridazines per g or 8 mmol N per g) with grafted di(pyridyl)pyridazines in a single step.
Concise Enantiocontrolled Synthesis of the A-Ring Precursor of Calcitriol from the Chiral Cyclohexadienone Synthon
Kamikubo, Takashi,Ogasawara, Kunio
, p. 1951 - 1952 (1995)
A new and concise enantiocontrolled route to the A-ring precursor of calcitriol is developed by utilizing the chiral cyclohexane-2,5-dienone synthon.
The use of optically active O-alkyl ester hydrochlorides of L-phenylalanine and L-tyrosine as chiral micellar media for the catalysis of diels-alder reactions
Caumul,Koonja,Namooya,Prayag,Joondan,Jhaumeer-Laulloo
, p. 509 - 518 (2017)
The effect of a range of O-alkyl ester hydrochloride surfactants derived from L-phenylalanine and L-tyrosine as catalysts on the Diels-Alder reaction between cyclopentadiene and methyl acrylate was studied. Both chain lengths (C8-C14) and head groups of the surfactants were found to influence the yield and selectivity of the Diels-Alder product. The C10 derivatives of both phenylalanine and tyrosine surfactants gave the highest yields and selectivity. Phenylalanine ester hydrochlorides showed better catalytic activity than the tyrosine derivatives. Adduct optimum yield was obtained at a concentration relating to their critical micelle concentration (CMC) values. The Diels-Alder reaction was also found to be favored in acidic condition (pH 3) as well as in the presence of lithium chloride (LiCl) as salting out agent.
Solvent effect as the result of frontier molecular orbital interaction. VII. The Retro-Diels-Alder reaction
Desimoni,Faita,Pasini,Righetti
, p. 1667 - 1674 (1992)
The solvent effect on the retro-Diels-Alder (R.D.A.) reaction of 1,4,4a,9a-tetrahydro-4a-methyl-(1α,4 α,4aα,9aα)-1,4-methanoanthracene-9,10-dione to 2-methyl-1,4-naphthoquinone and cyclopentadiene was investigated kinetically in 16 solvents. The hyperbolic relationship between the kinetic data and the Acceptor Number of the solvent is strong evidence that the solvent acts as an electrophile which lowers the activation energy of the reaction. Furthermore when these rate constants are plotted vs those of the previously investigated Diels-Alder (D.A.) reaction of 1,4-naphthoquinone and 2,3-dimenthylbutadiene, a linear relationships is obtained. The linearity of the graph is a good indication that the nature of the solvent effect is the same in both D.A. and R.D.A. reactions. The above relationships and the thermodynamic parameters strongly suggest that the R.D.A. reaction is a "late transition state" pericyclic reaction whose solvent effect derives from a specific interaction between the solvent and the product.
(E)- and (Z)-Prop-1-en-1-ol: Gas-phase Generation and Determination of Heats of Formation by Mass Spectrometry
Turecek, Frantisek
, p. 1374 - 1375 (1984)
The unstable (E)- and (Z)-prop-1-en-1-ol were generated in the gas phase and their heats of formation determined as -169 to -174 kJ mol-1.
Isopropenyl Acetoacetate and the Reaction of Diketene with Acetone
Hyatt, John A.
, p. 5102 - 5105 (1984)
The acid-catalyzed reaction of diketene with acetone to form 2,2,6-trimethyl-4H-1,3-dioxin-4-one, when conducted by using acetone-d6, yields a product with a high degree of deuterium scrambling.This scrambling is inconsistent with the intermediacy of either acetylketene or a 1,4-dipolar form of diketene in the reaction.Pathways involving isopropenyl acetoacetate or its protonated form are judged more compatible with the labeling results.Authentic isopropenyl acetoacetate was synthesized by using a retro-Diels-Alder route and was found to be converted to the title dioxinone under the diketene-acetone reaction conditions.
