18684-55-4Relevant academic research and scientific papers
Gold(I)-Catalyzed Cyclization-3-Aza-Cope-Mannich Cascade and Its Application to the Synthesis of Cephalotaxine
Sakai, Takeo,Okumura, Chise,Futamura, Masatoshi,Noda, Naotaka,Nagae, Akari,Kitamoto, Chiharu,Kamiya, Madoka,Mori, Yuji
supporting information, p. 4391 - 4395 (2021/05/26)
The discovery of a new gold(I)-catalyzed cascade reaction involving cyclization onto a vinylammonium, 3-aza-Cope rearrangement, and Mannich cyclization is reported. A variety of fused nitrogen heterocycles were prepared from simple cyclic tertiary amines using 1-5 mol % of a AuCl(PPh3)/Ag[C5(CN)5] cocatalyst system. The developed reaction was used in a study aimed at synthesizing cephalotaxine. A five-step operation from norhydrastinine provided demethylcephalotaxinone in 39.1% overall yield, which was transformed to (-)-cephalotaxine in two steps.
MERTK DEGRADERS AND USES THEREOF
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Paragraph 00862; 00863, (2020/01/31)
The present invention provides compounds, compositions thereof, and methods of using the same.
Synthesis and antibacterial activity of C-7 acylhydrazone derivatives of dehydroabietic acid
Zhou, Zhi,Zhou, Tingting
, p. 405 - 407 (2018/09/12)
Seven new C-7 acylhydrazone derivatives of dehydroabietic acid were synthesised from dehydroabietic acid through benzylic oxidation, condensation with hydrazine hydrate, followed by nucleophilic substitution reactions with a variety of substituted aromatic acids. The structures of the synthesised compounds were characterised by IR, 1H NMR and MS. The antibacterial activities of the synthesised compounds were evaluated by the disk diffusion method. Antibacterial activity studies showed that C-7 acylhydrazone derivatives of dehydroabietic acid exhibited inhibitory activities against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. Among the seven compounds, dehydroabietic acid p-fluorobenzoyl hydrazone showed the strongest inhibitory activity against B. subtilis and S. aureus.
A New Synthetic Route Towards Picealactone a from an Abietic Acid
Liao, Shengliang,Shen, Minggui,Song, Jie,Shang, Shibin,Rao, Xiaoping,Song, Zhanqian
, p. 658 - 660 (2017/10/06)
A new synthetic route towards picealactone A from an abietic acid, dehydroabietic acid, was introduced in this study. In this synthetic route, the picealactone A was synthesized by a tandem oxide/intramolecular esterification of 7-carbonyl dehydroabietic acid catalyzed by Yb(OTf)3.
Development of a selective activity-based probe for glycosylated LIPA
Schwaid, Adam G.,Ruangsiriluk, Wanida,Reyes, Allan R.,Cabral, Shawn,Rajamohan, Francis,Tu, Meihua,Ward, Jessica,Carpino, Philip A.
supporting information, p. 1993 - 1996 (2016/04/05)
Loss of LIPA activity leads to diseases such as Wolman's Disease and Cholesterol Ester Storage Disease. While it is possible to measure defects in LIPA protein levels, it is difficult to directly measure LIPA activity in cells. In order to measure LIPA activity directly we developed a LIPA specific activity based probe. LIPA is heavily glycosylated although it is unclear how glycosylation affects LIPA activity or function. Our probe is specific for a glycosylated form of LIPA in cells, although it labels purified LIPA regardless of glycosylation.
EIMS Fragmentation Pathways and MRM Quantification of 7α/β-Hydroxy-Dehydroabietic Acid TMS Derivatives
Rontani, Jean-Fran?ois,Aubert, Claude,Belt, Simon T.
, p. 1606 - 1616 (2015/08/18)
EI mass fragmentation pathways of TMS derivatives οf 7α/β-hydroxy-dehydroabietic acids resulting from NaBH4-reduction of oxidation products of dehydroabietic acid (a component of conifers) were investigated and deduced by a combination of (1) low energy CID-GC-MS/MS, (2) deuterium labeling, (3) different derivatization methods, and (4) GC-QTOF accurate mass measurements. Having identified the main fragmentation pathways, the TMS-derivatized 7α/β-hydroxy-dehydroabietic acids could be quantified in multiple reaction monitoring (MRM) mode in sea ice and sediment samples collected from the Arctic. These newly characterized transformation products of dehydroabietic acid constitute potential tracers of biotic and abiotic degradation of terrestrial higher plants in the environment. [Figure not available: see fulltext.]
Synthesis and BK channel-opening activity of novel N-acylhydrazone derivatives from dehydroabietic acid
Lv, Xia-Shi,Cui, Yong-Mei,Wang, He-Yun,Lin, Hai-Xia,Ni, Wei-Ya,Ohwada, Tomohiko,Ido, Katsutoshi,Sawada, Kohei
, p. 1023 - 1026 (2013/11/06)
A series of hydrazone and N-acylhydrazone derivatives of dehydroabietic acid were synthesized and evaluated for BK channel-opening activities in an assay system of CHO-K1 cells expressing hBKα channels. The assay results indicated that the activities of the investigated compounds were influenced by the physicochemical properties of the substituent at hydrazone moiety.
Bimetallic oxidative addition involving radical intermediates in nickel-catalyzed alkyl-alkyl Kumada coupling reactions
Breitenfeld, Jan,Ruiz, Jesus,Wodrich, Matthew D.,Hu, Xile
supporting information, p. 12004 - 12012 (2013/09/02)
Many nickel-based catalysts have been reported for cross-coupling reactions of nonactivated alkyl halides. The mechanistic understanding of these reactions is still primitive. Here we report a mechanistic study of alkyl-alkyl Kumada coupling catalyzed by a preformed nickel(II) pincer complex ([(N 2N)Ni-Cl]). The coupling proceeds through a radical process, involving two nickel centers for the oxidative addition of alkyl halide. The catalysis is second-order in Grignard reagent, first-order in catalyst, and zero-order in alkyl halide. A transient species, [(N2N)Ni-alkyl 2](alkyl2-MgCl), is identified as the key intermediate responsible for the activation of alkyl halide, the formation of which is the turnover-determining step of the catalysis.
Design, synthesis, and characterization of BK channel openers based on oximation of abietane diterpene derivatives
Cui, Yong-Mei,Yasutomi, Eriko,Otani, Yuko,Ido, Katsutoshi,Yoshinaga, Takashi,Sawada, Kohei,Ohwada, Tomohiko
experimental part, p. 8642 - 8659 (2011/02/25)
Oxime ether derivatives at the benzylic position of unsubstituted, dichloro, trichloro, and monobromo derivatives of the aromatic C-ring of dehydroabietic acid and podocarpic acid were synthesized and evaluated as BK channel openers in an assay system of CHO-K1 cells expressing hBKα channels. Detailed SAR analysis showed that the oximation was particularly effective in the cases of dehydroabietic acid derivatives, and some of these oxime derivatives showed more potent BK channel activities than the standard compound, NS1619. The present studies provide a new structural basis for development of efficient BK channel openers.
Oxidation products of abietic acid and its methyl ester
Prinz, Sonja,Muellner, Ursula,Heilmann, Joerg,Winkelmann, Karin,Sticher, Otto,Haslinger, Ernst,Huefner, Antje
, p. 1530 - 1534 (2007/10/03)
Abietic acid (1) and its methyl ester (2) were investigated under various storage conditions to provide an indication of their preferred oxidation mechanisms and to investigate the most susceptible positions for modification in the abietane skeleton. Six
