5524-25-4Relevant academic research and scientific papers
Cytochrome P450-Catalyzed Hydroxylation Initiating Ether Formation in Platensimycin Biosynthesis
Rudolf, Jeffrey D.,Dong, Liao-Bin,Zhang, Xiao,Renata, Hans,Shen, Ben
supporting information, p. 12349 - 12353 (2018/09/27)
Platensimycin (PTM) and platencin (PTN) are potent and selective inhibitors of bacterial and mammalian fatty acid synthases. The regio- and stereospecificity of the ether oxygen atom in PTM, which PTN does not have, strongly contribute to the selectivity and potency of PTM. We previously reported the biosynthetic origin of the 11S,16S-ether moiety by characterizing the diterpene synthase PtmT3 as a (16R)-ent-kauran-16-ol synthase and isolating 11-deoxy-16R-hydroxylated congeners of PTM from the ptmO5 mutant. PtmO5, a cytochrome P450, was proposed to catalyze formation of the ether moiety in PTM. Here we report the in vitro characterization of PtmO5, revealing that PtmO5 stereoselectively hydroxylates the C-11 position of the ent-kaurane scaffold resulting in an 11S,16R-diol intermediate. The ether moiety, the oxygen of which originates from the P450-catalyzed hydroxylation at C-11, is formed via cyclization of the diol intermediate. This study provides mechanistic insight into ether formation in natural product biosynthetic pathways.
Methyl and p-Bromobenzyl Esters of Hydrogenated Kaurenoic Acid for Controlling Anthracnose in Common Bean Plants
Mota, Suellen F.,Oliveira, Denilson F.,Heleno, Vladimir C. G.,Soares, Ana Carolina F.,Midiwo, Jacob O.,Souza, Elaine A.
, p. 1489 - 1495 (2017/03/11)
Kaurenoic acid derivatives were prepared and submitted to in vitro assays with the fungus Colletotrichum lindemuthianum, which causes anthracnose disease in the common bean. The most active substances were found to be methyl and p-bromobenzylesters, 7 and
Synthesis, in vitro antimalarial activity and in silico studies of hybrid kauranoid 1,2,3-Triazoles Derived from Naturally Occurring Diterpenes
De Santos, Juliana O.,Pereira, Guilherme R.,Brand?o, Geraldo C.,Borgati, Tatiane F.,Arantes, Lucas M.,De Paula, Renata C.,Soares, Luciana F.,Do Nascimento, Maria F.A.,Ferreira, Marlia R.C.,Taranto, Alex G.,Varotti, Fernando P.,De Oliveira, Alaíde B.
, p. 551 - 565 (2016/03/19)
We herein report the synthesis of hybrid kauranoid molecules of type 1,2,3-triazole-1,4-disubstituted aiming to improve the antimalarial activity of kaurenoic and xylopic acids. The CuI-catalyzed cycloaddition of azides and kauranoid terminal a
Synthesis, cytotoxicity and antiplasmodial activity of novel ent-kaurane derivatives
Batista, Ronan,Garcia, Pablo A.,Castro, Maria Angeles,Miguel Del Corral, Jose M.,Speziali, Nivaldo L.,De P. Varotti, Fernando,De Paula, Renata C.,Garcia-Fernandez, Luis F.,Francesch, Andres,San Feliciano, Arturo,De Oliveira, Alaide B.
, p. 168 - 176 (2013/05/09)
This paper reports on the syntheses and spectrometric characterisation of eleven novel ent-kaurane diterpenoids, including a complete set of 1H, 13C NMR and crystallographic data for two novel ent-kaurane diepoxides. Moreover, the antineoplastic cytotoxicity for kaurenoic acid and the majority of ent-kaurane derivatives were assessed in vitro against a panel of fourteen cancer cell lines, of which allylic alcohols were shown to be the most active compounds. The good in vitro antimalarial activity and the higher selectivity index values observed for some ent-kaurane epoxides against the chloroquine-resistant W2 clone of Plasmodium falciparum indicate that this class of natural products may provide new hits for the development of antimalarial drugs.
Cytotoxic and apoptosis-inducing activities of steviol and isosteviol derivatives against human cancer cell lines
Ukiya, Motohiko,Sawada, Shingo,Kikuchi, Takashi,Kushi, Yasunori,Fukatsu, Makoto,Akihisa, Toshihiro
, p. 177 - 188 (2013/04/23)
Seventeen steviol derivatives, i.e., 2-18, and 19 isosteviol derivatives, i.e., 19-37, were prepared from a diterpenoid glycoside, stevioside (1). Upon evaluation of the cytotoxic activities of these compounds against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK-BR-3) cancer cell lines, nine steviol derivatives, i.e., 5-9 and 11-14, and five isosteviol derivatives, i.e., 28-32, exhibited activities with single-digit micromolar IC50 values against one or more cell lines. All of these active compounds possess C(19)-O-acyl group, and among which, ent-kaur-16-ene-13,19-diol 19-O-4′,4′,4′-trifluorocrotonate (14) exhibited potent cytotoxicities against four cell lines with IC50 values in the range of 1.2-4.1 μM. Compound 14 induced typical apoptotic cell death in HL60 cells upon evaluation of the apoptosis-inducing activity by flow-cytometric analysis. These results suggested that acylation of the 19-OH group of kaurane- and beyerane-type diterpenoids might be useful for enhancement of their cytotoxicities with apoptosis-inducing activity. Copyright
Synthesis and anti-inflammatory activity of ent-kaurene derivatives
Hueso-Falcón, Idaira,Cuadrado, Irene,Cidre, Florencia,Amaro-Luis, Juan M.,Ravelo, ángel G.,Estevez-Braun, Ana,De Las Heras, Beatriz,Hortelano, Sonsoles
experimental part, p. 1291 - 1305 (2011/04/23)
A series of kaurene derivatives (1-63) were prepared and evaluated for anti-inflammatory activity. Thirteen of the tested compounds were able to inhibit NO production with an IC50 between 2 and 10 μM. Compounds 11, 12, 14 and 23 showed low perc
Synthesis and induction of apoptosis signaling pathway of ent-kaurane derivatives
Hueso-Falcón, Idaira,Girón, Natalia,Velasco, Pilar,Amaro-Luis, Juan M.,Ravelo, Angel G.,Heras, Beatriz de las,Hortelano, Sonsoles,Estevez-Braun, Ana
experimental part, p. 1724 - 1735 (2010/04/29)
Thirty one ent-kaurane derivatives were prepared from kaurenoic acid (1), grandiflorenic acid (16), 15α-acetoxy-kaurenoic acid (26) and 16α-hydroxy-kaurenoic acid (31). They were tested for their ability to inhibit cell viability in the mouse leukemic macrophagic RAW 264.7 cell line. The most effective compounds were 12, 20, 21, and 23. These were selected for further evaluation in other human cancer cell lines such as Hela, HepG2, and HT-29. Similar effects were obtained although RAW 264.7 cells were more sensitive. In addition, these compounds were significantly less cytotoxic in non-transformed cells. The apoptotic potential of the most active compounds was investigated and they were able to induce apoptosis with compound 12 being the best inducer. The caspase-3, -8 and -9 activities were measured. The results obtained showed that compounds 12, 21, and 23 induce apoptosis via the activation of caspase-8, whereas compound 20 induces apoptosis via caspase-9. Immunoblot analysis of the expression of p53, Bax, Bcl-2, Bcl-xl, and IAPs in RAW 264.7 cells was also carried out. When cells were exposed to 5 μM of the different compounds, expression levels of p53 and Bax increased whereas levels of antiapoptotic proteins such as Bc1-2, Bc1-x1, and IAPs decreased. In conclusion, kaurane derivatives (12, 20, 21, and 23) induce apoptosis via both the mitochondrial and membrane death receptor pathways, involving the Bcl-2 family proteins. Taken together these results provide a role of kaurane derivatives as apoptotic inducers in tumor cells.
Inhibition of Na+,K+-ATPase activity by (-)-ent-Kaur-16-en-19-oic acid and its derivatives
Ngamrojnavanich, Nattaya,Sirimongkon, Supaporn,Roengsumran, Sophon,Petsom, Amorn,Kamimura, Hishashi
, p. 555 - 556 (2007/10/03)
The diterpene, (-)-ent-kaur-16-en-19-oic acid, from Croton oblongifolius was identified as an Na+,K+-ATPase inhibitor. This compound exhibits an IC50 of 2.2 × 10-5 M against crude enzyme Na+,K+-ATPase from rat brain. The semi-synthetic derivatives, (-)-methyl kaur-16-en-19-oate, (-)-kaur-16-en-19-ol, (-)-16β,17-epoxykauran-19-oic acid and (-)-17-hydroxykaur-15-en-19-oic acid were also tested and their IC50 were 5.5 × 10-4, 5.0 × 10-4, 4.8 × 10-4 and 6.0 × 10-4 M, respectively.
Antimicrobial terpenoids from the oleoresin of the Peruvian medicinal plant Copaifera paupera
Tincusi, Benigna M.,Jimenez, Ignacio A.,Bazzocchi, Isabel L.,Moujir, Laila M.,Mamani, Zulma A.,Barroso, Jose P.,Ravelo, Angel G.,Hernandez, Basilio V.
, p. 808 - 812 (2007/10/03)
Twelve known diterpenes 1-11 and 13, and three known sesquiterpenes 14-16, along with a new C20-C15 terpenoid 17, with a structure based on an unprecedented skeleton in which a labdane diterpene is linked to a monocyclic sesquiterpene by an ester bridge, were isolated from the oleoresin of the Peruvian medicinal plant Copaifera paupera (Herzog) Dwyer (Leguminosae). Their structures were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlation NMR experiments (COSY, ROESY, HMQC and HMBC), and by comparison with data in the literature. The leishmanicidal, antimicrobial, cytotoxic, and aldose reductase inhibitory activities were studied. Compounds 1 and 11 showed significant antimicrobial activity (MIC 10μg/ml) against Gram-positive bacteria, comparable with cephotaxime used as control. Compound 2 exhibited moderate cytotoxic activity against four cancer cell lines.
Total Syntheses of (-)-Methyl Atis-16-en-19-oate, (-)-Methyl Kaur-16-en-19-oate, and (-)-Methyl Trachyloban-19-oate by a Combination of Palladium-Catalyzed Cycloalkenylation and Homoallyl-Homoallyl Radical Rearrangement
Toyota, Masahiro,Wada, Toshihiro,Ihara, Masataka
, p. 4565 - 4570 (2007/10/03)
Asymmetric total syntheses of (-)-methyl atis-16-en-19-oate (1c), (-)-methyl kaur-16-en-19-oate (2c), and (-)-methyl trachyloban-19-oate (3c) have been achieved by employing a hybrid strategy of palladium-catalyzed cycloalkenylation and homoallyl-homoallyl radical rearrangement. The common synthetic intermediate 5 was prepared from 2-allylcyclohexanone (4) with 98% ee using d'Angelo's asymmetric Michael addition. A series of functional group modifications in 5 via palladium-catalyzed cycloalkenylation led to (+)-14, which had already been prepared by us as racemate. (-)-Methyl atis-16-ene-19-oate (1c) was generated via homoallyl-homoallyl radical rearrangement. On the other hand, Wolff-Kishner reduction of 18 followed by esterification yielded (-)-methyl kaur-16-en-19-oate (2c) together with (-)-methyl trachyloban-19-oate (3c).
