1231-74-9Relevant academic research and scientific papers
Functionalisation of tetraalkylsilanes derived from C-H activation; Towards annulations of diterpenoids
Harris, Paul W.R.,Rickard, Clifton E.F.,Woodgate, Paul D.
, p. 172 - 190 (2000)
Vinyl trialkylsilanes are efficient substrates for use in the ortho alkylation of aromatic ketones catalysed by zerovalent ruthenium complexes, giving, e.g. (2-trimethylsilylethyl)acetophenones. Methods for the selective desilylation-functionalisation of such tetraalkylsilanes are investigated. Some diterpenoid tetraalkylsilanes derived from the ruthenium-catalysed insertion of vinyltrimethylsilane have been functionalised by benzylic bromination of an ArCH2CH2SiMe3 fragment with NaBrO3-Na2S2O5 (optimally), leading to a 1,2-dibromoethyl derivative. Further transformations culminated in the overall conversion of ArCH2CH2SiMe3 into ArCOCH3. Attempted aldol coupling of the resulting 1,4-diketone provoked skeletal reorganisation. A tetraalkylsilane was converted into a silanol (ArCH2CH2SiMe2OH) by the action of aluminium chloride and water, but further oxidation of this silanol to the primary alcohol (ArCH2CH2OH) was unsuccessful.
Copper-catalyzed cross-coupling reactions of methyl 13-Iodo-O- methylpodocarpate and amides
Nguyen, Dao M.,Miles, D. Howard
, p. 2829 - 2836 (2009)
Copper iodide was utilized as a relatively inexpensive catalyst (versus palladium) for the high-yield synthesis of amide derivatives of podocarpic acid. The reaction involved the one-step cross-coupling reaction of methyl 13-iodo-O-methylpodocarpate with amides.
Copper-catalyzed cross-coupling reactions of methyl 13-iodo-o- methylpodocarpate and alcohols
Yalavarty, Manjeera,Paradise, Courtney M.,Klein, Travis A. L.,Miles, D. Howard
, p. 1625 - 1630 (2010)
Copper iodide was utilized as a relatively inexpensive catalyst for the synthesis of podocarpic acid ether derivatives in excellent yields through the one-step cross-coupling reaction of methyl 13-iodo-O-methylpodocarpate with alcohols. Copyright
Late-stage C-H amination of abietane diterpenoids
Lapuh, María Ivana,Dana, Alejandro,Di Chenna, Pablo H.,Darses, Benjamin,Durán, Fernando J.,Dauban, Philippe
supporting information, p. 4736 - 4746 (2019/05/24)
This study aims at highlighting the synthetic versatility of the rhodium-catalyzed C-H amination reactions using iodine(iii) oxidants for the late-stage functionalization of natural products. Inter-and intramolecular nitrene insertions have been performed from various abietane diterpenoids, leading to the amination of the C-3, C-6, C-7, C-11 and C-15 positions. Ca. 20 aminated compounds have been isolated with yields of up to 86% and high levels of regio-, chemo-and stereoselectivities.
Phenolic diterpenoid derivatives as anti-influenza a virus agents
Dang, Zhao,Jung, Katherine,Zhu, Lei,Xie, Hua,Lee, Kuo-Hsiung,Chen, Chin-Ho,Huang, Li
, p. 355 - 358 (2015/03/30)
A series of diterpenoid derivatives based on podocarpic acid were synthesized and evaluated as anti-influenza A virus agents. Several of the novel podocarpic acid derivatives exhibited nanomolar activities against an H1N1 influenza A virus (A/Puerto Rico/8/34) that was resistant to two anti-influenza drugs, oseltamivir and amantadine. This class of compounds inhibits the influenza virus by targeting the viral hemagglutinin-mediated membrane fusion. These results indicated that podocarpic acid derivatives may serve as potential drug candidates to fight drug-resistant influenza A virus infections.
Design, synthesis and characterization of podocarpate derivatives as openers of BK channels
Cui, Yong-Mei,Yasutomi, Eriko,Otani, Yuko,Yoshinaga, Takashi,Ido, Katsutoshi,Sawada, Kohei,Ohwada, Tomohiko
scheme or table, p. 5197 - 5200 (2009/05/07)
We found that the podocarpic acid structure provides a new scaffold for chemical modulators of large-conductance calcium-activated K+ channels (BK channels). Structure-activity analysis indicates the importance of both the arrangement (i.e., location and orientation) of the carboxylic acid functionality of ring A and the hydrophobic region of ring C for expression of BK channel-opening activity.
Addition-protonation reactions of (η6-arene)tricarbonylchromium(0) complexes of podocarpic acid derivatives: synthesis of steroidal alicyclic skeletons
Cambie, Richard C.,Rutledge, Peter S.,Stevenson, Ralph J.,Woodgate, Paul D.
, p. 199 - 210 (2007/10/02)
Functionalization of the (η6-arene)tricarbonylchromium(0) complexes of some podocarpic acid (1) derivatives has been achieved through the addition-protonation route.The resulting dienol ethers underwent acid-promoted hydrolysis giving enones wh
Total Synthesis of (+)-Podocarpic and (+)-Lambertic Acids
Hao, Xiao-jiang,Node, Manabu,Fuji, Kaoru
, p. 1505 - 1510 (2007/10/02)
A concise synthesis, from the chiral nitroalkene 1a, of (+)-podocarpic acid is described.This was transformed into (+)-lambertic acid via a chromium complex.
Directed ortho Metallation Studies on Podocarpic Acid Derivatives: Advantageous Use of a LICKOR Base
Cambie, Richard C.,Higgs, Paul I.,Lee, Kee Chee,Metzler, Michael R.,Rutledge, Peter S.,at al.
, p. 1465 - 1477 (2007/10/02)
Methyl 13-(N,N-diethylcarbamoyl)-12-methoxypodocarpa-8,11,13-trien-19-oate (2), 13-(N,N-diethylcarbamoyl)-12,19-dimethoxypodocarpa-8,11,13-triene (8) and N,N-diethyl-2-methoxy-4,5-dimethylbenzamide (15) were prepared for studies involving lithiation directed ortho to the tertiary amide group, in which the use of a LICKOR base was advantageous.Some dynamic features of the n.m.r. spectra of the amides are discussed.Oxazoline derivatives of both the monocyclic and diterpenoid compounds were synthesized.
Syntheses of Confertifolin, Winterin and Isodrimenin Congeners from Podocarpic Acid
Cambie, Richard C.,Grimsdale, Andrew C.,Rutledge, Peter S.,Woodgate, Paul D.
, p. 485 - 501 (2007/10/02)
Podocarpic acid (11) has been converted into the congener (5) of confertifolin (4) through the o-quinone (29) formed by oxidations of the catechol monoether (15) and the 13-amine (16) with Fremy's salt.Oxidation of the methyl ether (12) afforded the p-quinone (44) which was converted into the congener (6) of winterin (7).Podocarpic acid has also been converted into the congener (8) of isodrimenin (9) through the catechol derivative (37).
