74087-85-7Relevant articles and documents
Intramolecular epoxide ring opening cyclisation reactions involving guanidines
Al Shuhaib, Zainab,Arndt, Marcel,Dennis, Mark,Evans, Daniel M.,Jones, Iestyn,Leitmann, Vera,Murphy, Patrick J.,Roberts, Dion,Rowles, Richard,Sadaghiani, Yones K.,Thornhill, Andrew J.,Nash, Robert J.,Hollinshead, Jackie,Bartholomew, Barbara,Tizzard, Graham J.,Coles, Simon J.
, p. 1 - 47 (2017)
The cyclisation of N-allyl- and N-homoallylguanidines using DMDO leading to the formation of novel 5- and 6-membered guanidine heterocycles is reported. Several of the products formed displayed weak inhibition of glycosidase enzymes.
Studies on the ketone-catalyzed decomposition of caroate in aqueous alkaline medium
Selvararani,Medona,Ramachandran
, p. 483 - 488 (2005)
The kinetics of ketone-catalyzed decomposition of caroate (peroxomonosulfate) was studied in aqueous alkaline medium at 25°C. The rate follows simple second-order kinetics, first order in each (Ketone) and [PMS]. The rate constant values are independent of hydroxide ion concentrations over the range from 0.05 M to 0.15 M. The experimental results suggest that the nucleophilic addition of SO5-2 ion at the carbonyl carbon leads to the formation of oxirane intermediate in the rate-determining step. Oxirane reacts rapidly with another SO52- to give the parent ketone, oxygen, and SO42-. The observed substituent effect on the activation energy EA and Arrhenius (A) factor suggests that the electron-donating substituents stabilize the activated state and make the entropy of activation more negative. This can be explained by the fact that the mechanism of oxirane formation shifts from concentric to nonconcentric process as we go from acetone to 3-hexanone.
Conversion of Isocyanates to Nitro Compounds with Dimethyldioxirane in Wet Acetone
Eaton, Philip E.,Wicks, Gene E.
, p. 5353 - 5355 (1988)
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Identification of amino acid and glutathione N-conjugates of Toosendanin: Bioactivation of the furan ring mediated by CYP3A4
Yu, Jinghua,Deng, Pan,Zhong, Dafang,Chen, Xiaoyan
, p. 1598 - 1609 (2014)
Toosendanin (TSN) is a hepatotoxic triterpenoid extracted from Melia toosendan Sieb et Zucc. Considering that TSN contains the structural alert of the furan ring, it is believed that bioactivation of TSN may be responsible for its toxicity. Herein, the bioactivation potential and metabolism profiles of TSN were investigated. After an oral administration of 10 mg/kg TSN to rats, esterolysis and conjugation with amino acids were identified as the main metabolic pathways. The same types of conjugates were detected in liver microsomes in an NADPH-dependent manner. According to the remaining amount of the parent drug, the reactivity of trapping reagents with TSN reactive metabolites was sorted in a decreasing order of Nα-(tert-butoxycarbonyl)-L-lysine (Boc-Lys) > alanine, lysine, taurine, phenylalanine, serine, glutamic acid, glycine, and glutathione (GSH) > cysteine. No conjugates were observed in NADPH and N-acetyl cysteine (NAC)-supplemented human liver microsomal incubations. Further phenotyping studies and the chemical synthesis of the major conjugated standards proved that TSN was bioactivated by CYP3A4 and yielded a cis-butene-1,4-dial intermediate, which was prone to undergo 1,2-addition with the amino group of amino acids and GSH to form 3-pyrroline-2-one adducts. The sulfydryl group of GSH also attacked the intermediate and yielded S-conjugates by 1,4- or 1,2-addition, which would form pyrrole conjugates by further reacting with the amino group. Compared to the well-recognized Sconjugation of the furan ring, N-conjugation with multiple amino acids and GSH played a more important part in the elimination of reactive metabolites of TSN. The significance of these conjugates requires further investigation. (Chemical Equation Presented).
In Vitro DNA Adduction Resulting from Metabolic Activation of Diosbulbin B and 8-Epidiosbulbin e Acetate
Lin, Dongju,Li, Weiwei,Tian, Xutong,Peng, Ying,Zheng, Jiang
, p. 38 - 48 (2019)
Diosbulbin B (DBB) and 8-epidiosbulbin E acetate (EEA), belonging to furan-containing diterpenoid lactones, are the primary components of Dioscorea bulbifera L. (DB), a traditional Chinese medicine herb. Our earlier studies indicated that consumption of DBB or EEA induced acute hepatotoxicities. Both DBB and EEA were bioactivated by P450 3A4 to generate the corresponding cis-enedial reactive metabolites which are associated with the hepatotoxicities. It has been proposed that the electrophilic intermediates attack cellular nucleophiles such as protein or DNA, thought to be a mechanism of triggering toxicities. The purposes of our present study were to define the interaction of the electrophilic reactive metabolites originating from DBB and EEA with 2′-deoxyguanosine (dGuo), 2′-deoxycytidine (dCyd), and 2′-deoxyadenosine (dAdo) and to characterize DNA adducts arising from the reactive metabolites of DBB and EEA. The reactive metabolites of DBB and EEA were found to covalently bind to the exocyclic and endocyclic nitrogens of dCyd, dGuo, and dAdo to generate oxadiazabicyclo[3.3.0]octaimine adducts. The reactive metabolites of DBB and EEA also attacked dGuo, dAdo, and dCyd of calf thymus DNA. The DNA adducts possibly contribute to the toxicologies of DBB and EEA.
The Smelling Principle of Vetiver Oil, Unveiled by Chemical Synthesis
Ouyang, Jie,Bae, Hanyong,Jordi, Samuel,Dao, Quang Minh,Dossenbach, Sandro,Dehn, Stefanie,Lingnau, Julia B.,Kanta De, Chandra,Kraft, Philip,List, Benjamin
, p. 5666 - 5672 (2021)
Vetiver oil, produced on a multiton-scale from the roots of vetiver grass, is one of the finest and most popular perfumery materials, appearing in over a third of all fragrances. It is a complex mixture of hundreds of molecules and the specific odorant, responsible for its characteristic suave and sweet transparent, woody-ambery smell, has remained a mystery until today. Herein, we prove by an eleven-step chemical synthesis, employing a novel asymmetric organocatalytic Mukaiyama–Michael addition, that (+)-2-epi-ziza-6(13)en-3-one is the active smelling principle of vetiver oil. Its olfactory evaluation reveals a remarkable odor threshold of 29 picograms per liter air, responsible for the special sensuous aura it lends to perfumes and the quasi-pheromone-like effect it has on perfumers and consumers alike.
Kraft pulp bleaching using dimethyldioxirane: Stability of the oxidants
Bouchard
, p. 232 - 237 (1996)
Dimethyldioxirane (DMD) is a cyclic peroxide made by oxidizing acetone with peroxymonosulfate (PMS) in water buffered at pH 7.5 using sodium bicarbonate. It has been shown that DMD generation can be achieved in situ within a pulp suspension allowing very selective TCF bleaching of kraft pulp. This process involves simultaneous generation of DMD, reaction of PMS and DMD with residual lignin, and spontaneous decomposition of both oxidants. The first part of this work is a kinetics study of the decomposition of PMS and DMD as a function of pH under conditions similar to those for in situ bleaching. The effect of chelation as well as the effect of transition metal ions on decomposition rate was also investigated. DMD is very sensitive to pH and its half-life is very short under alkaline conditions. The presence of any transition metal ion that can be involved in a one-electron transfer is detrimental to DMD stability. However, fast reaction of DMD with pulp almost counteracts the effect of metal ions.
Regioselectivities of (4 + 3) cycloadditions between furans and oxazolidinone-substituted oxyallyls
Lohse, Andrew G.,Krenske, Elizabeth H.,Antoline, Jennifer E.,Houk,Hsung, Richard P.
, p. 5506 - 5509 (2010)
The (4 + 3) cycloadditions of oxazolidinone-substituted oxyallyls and unsymmetrically substituted furans lead to syn regioselectivity when the furan has a 2-Me or 2-COOR substituent, while anti regioselectivity is obtained with a 3-Me or 3-COOR group. DFT calculations are performed to explain the selectivities. The reactivities and regioselectivities are consistent with the ambiphilic reactivity of amino-oxyallyls with furans.
Congo red and nigrosine dye degradation using dimethyl dioxirane as an oxidising agent
Rose, A. Leema,Vinotha, S.
, p. 1221 - 1228 (2021/11/17)
The advanced oxidation of Congo red (CR) and Nigrosine (NI) using the combined action of dimethyl dioxirane as an oxidising agent is described in this study. The effects of several parameters, such as the concentration of the oxidising agent, the initial dye concentration, and the pH, have been investigated. At room temperature, the oxidising agent dimethyl dioxirane was employed to test the degradation of CR and NI dyes. On the degradation efficiency of CR and NI, pH’s effects, oxidising agent, and initial dye concentration were examined. The absorbance of CR and NI dyes before and after degradation was measured using UV-Visible spectroscopy. The functional group existing in the dyes before and after degradation was determined using FT-IR spectroscopy.
Derivatization reaction of triacetylpyranosyldihydropyrrole and application of derivative products
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Paragraph 0018-0026, (2020/05/01)
The invention discloses a derivatization reaction of triacetylpyranosyldihydropyrrole and application of derivative products. A compound 1, namely triacetylpyranosyldihydropyrrole, is used as a reaction substrate. The reaction substrate is subjected to an addition reaction of a pyrrole ring double bond to obtain a compound 2; the reaction substrate is subjected to an epoxidation reaction of a pyrrole ring double bond to obtain a compound 3; the reaction substrate is subjected to a ring-opening reaction of a pyranose ring to obtain a compound 4; and the reaction substrate is subjected to a protective reaction to obtain a compound 5. The invention also discloses application of derivative products, the compounds 2-5, in the preparation of drugs for inhibiting proliferation of human breast cancer cells MCF-7 and application in the preparation of drugs for inhibiting activity of acetylcholinesterase and butyrylcholinesterase. According to the invention, a variety of derivatization reactionscan be performed to prepare the drug compounds with effects of tumor resistance and cholinesterase activity inhibition, and the derivatization reaction process has characteristics of mild reaction conditions, simple operation and high reaction yield.
