25458-46-2Relevant academic research and scientific papers
Platinum-catalyzed α,β-unsaturated carbene formation in the formal syntheses of frondosin B and liphagal
Huynh, Khoi Q.,Seizert, Curtis A.,Ozumerzifon, Tarik J.,Allegretti, Paul A.,Ferreira, Eric M.
supporting information, p. 294 - 297 (2017/11/28)
Formal syntheses of tetracyclic terpenoids frondosin B and liphagal are described. Both synthetic routes rely on the use of platinum-catalyzed α,β-unsaturated carbene formation for the key C-C bond forming transformations. The successful route toward frondosin B utilizes a formal (4 + 3) cycloaddition, while the liphagal synthesis features the vinylogous addition of an enol nucleophile as a key step. Both synthetic routes are discussed, revealing insights into structural requirements in the catalytic a,β-unsaturated carbene reaction manifold.
Bismuth trichloride–mediated cleavage of phenolic methoxymethyl ethers
Obaro-Best, Oghale,Reed, Jack,Norfadilah, Alya A. F. B.,Monahan, Ryan,Sunasee, Rajesh
supporting information, p. 586 - 593 (2016/06/08)
A simple and efficient method for removal of phenolic methoxymethyl ethers in the presence of 30?mol% of bismuth trichloride in acetonitrile/water is described. Notable features of the cleavage protocol entail use of an ecofriendly bismuth reagent, ease of handling, low cost, operational simplicity, and good functional group compatibility. A number of structurally varied phenolic methoxymethyl ethers were cleaved in good to excellent yields.
SUBSTITUTED BENZALDEHYDE COMPOUNDS AND METHODS FOR THEIR USE IN INCREASING TISSUE OXYGENATION
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Paragraph 0170, (2013/07/19)
Provided are substituted benzaldehydes and derivatives thereof that act as allosteric modulators of hemoglobin, methods and intermediates for their preparation, pharmaceutical compositions comprising the modulators, and methods for their use in treating disorders mediate by hemoglobin and disorders that would benefit from increased tissue oxygenation.
[InCl4]: An efficient catalyst-medium for alkoxymethylation of alcohols and their interconversion to acetates and TMS-ethers
Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza,Mirjafari, Arsalan
experimental part, p. 568 - 579 (2012/05/05)
A simple, green and chemoselective method for methoxymethylation and ethoxymethylation of primary and secondary alcohols using a Lewis acidic room temperature ionic liquid, [C4mim][InCl4], as catalyst and reaction medium under ambient temperature, microwave and ultrasonic irradiations is reported. In this catalytic system, the corresponding MOM-and EOM-ethers are obtained in excellent yields and in short reaction times. Furthermore, this catalytic system was used for mild and efficient transformations of these protected alcohols to their corresponding acetates and trimethylsilyl ethers under thermal conditions and microwave and ultrasonic irradiations.
The reaction of acetal-type protective groups in combination with TMSOTf and 2,2′-bipyridyl; Mild and chemoselective deprotection and direct conversion to other protective groups
Fujioka, Hiromichi,Minamitsuji, Yutaka,Kubo, Ozora,Senami, Kento,Maegawa, Tomohiro
experimental part, p. 2949 - 2960 (2011/05/12)
A mild and chemoselective deprotection method of various acetal-type protective groups, such as MOM, MEM, BOM, and SEM ethers, has been developed. The combination of TMSOTf and 2,2′-bipyridyl was very effective for the deprotection, and the reaction proceeded via the formation of pyridinium intermediates, which were hydrolyzed to the corresponding alcohols in good to high yields. The features of this method are mild (almost neutral) reaction conditions and the tolerability of acid-sensitive functional groups. This method is also applicable for the direct conversion of MOM ether to BOM or SEM ether using the appropriate alcohols instead of H2O.
Remarkable effect of 2,2′-bipyridyl: Mild and highly chemoselective deprotection of methoxymethyl (MOM) ethers in combination with TMSOTf (TESOTf)-2,2′-bipyridyl
Fujioka, Hiromichi,Kubo, Ozora,Senami, Kento,Minamitsuji, Yutaka,Maegawa, Tomohiro
supporting information; experimental part, p. 4429 - 4431 (2009/12/29)
The remarkable effect of 2,2′-bipyridyl led to the successful development of the mild and highly chemoselective deprotection method of methoxymethyl (MOM) ethers using the combination of TMSOTf (or TESOTf) and 2,2′-bipyridyl; this method can be applied to the direct conversion of the MOM group to other ethereal protective groups (e.g. benzyloxymethyl) with the corresponding alcohols. The Royal Society of Chemistry 2009.
Design, synthesis and biological evaluation of novel riccardiphenol analogs
Kumar, Srinivas K.,Amador, Maria,Hidalgo, Manuel,Bhat, Sujata V.,Khan, Saeed R.
, p. 2873 - 2880 (2007/10/03)
A novel, facile, high yield, and less cumbersome synthesis of riccardiphenol analogs is described. The synthesized compounds were characterized and assessed for its in vitro activity in a panel of human cancer cell lines of differing origin: HuCCT-1, BxPC3, Panc-1, Mia-Paca, A431, Hep2, and HN006. HuCCT-1 was derived from an intrahepatic cholangiocarcinoma; BxPC3, Mia-Paca, and Panc-1 were derived from pancreatic cancers; A431 was derived from a vulvar epithelial carcinoma; and Hep2 and HN006 were derived from squamous cell carcinomas of the head and neck. The cytotoxicity of a newly developed riccardiphenol analog against human cancer cell lines was assessed. The cancer cells exhibited varying sensitivities to the compound, with IC50 values from 30 to 50 μM. This susceptibility was particularly interesting in the case of lines such as Hep2 and BxPC3 that are resistant to classic cytotoxic drugs as well as some targeted agents. These results demonstrate that the novel riccardiphenol analog has effective action against human-derived cancer cell in vitro.
2-Phosphanylphenolate Nickel Catalysts for the Polymerization of Ethylene
Heinicke, Joachim,Koehler, Martin,Peulecke, Normen,He, Mengzhen,Kindermann, Markus K.,Keim, Wilhelm,Fink, Gerhard
, p. 6093 - 6107 (2007/10/03)
The previously unknown methallylnickel 2-diorganophosphanylphenolates (R=Ph, cHex) were synthesized and found to catalyze the polymerization of ethylene. To explore the potential for ligand-tuning, a variety of P-alkyl- and P-phenyl-2-phosphanylphenols wa
Enantioselective synthesis of cordiachromene
Bouzbouz, Samir,Goujon, Jean-Yves,Deplanne, Jerome,Kirschleger, Bernard
, p. 3223 - 3228 (2007/10/03)
An enantioselective synthesis of cordiachromene is described. An allylic alcohol moiety is first attached in the o-position to the methoxymethoxy substituent in 1-methoxy-4-methoxymethoxybenzene. Then chirality is introduced successively through asymmetric Sharpless epoxidation on the allylic alcohol moiety and regioselective ring-opening. The chiral diol prepared is then cyclized to chromanmethanol with total retention of configuration. Chromenemethanol is obtained after bromination and dehydrobromination. The total synthesis is achieved by reaction between the tosylated chromene chiral moiety and an organomagnesium prenylated compound.
Facile methods for the direct conversions of aryl acetates into the corresponding methoxymethyl ethers or silyl ethers
Oriyama, Takeshi,Noda, Kojiro,Sugawara, Satomi
, p. 2217 - 2223 (2007/10/03)
Direct conversion of aryl acetates into aryl methoxymethyl ethers or aryl trialkylsilyl ethers was readily accomplished by treatment with methoxymethyl bromide or trialkylsilyl trifluoromethanesulfonate, respectively, in the presence of sodium methoxide.
