6138-90-5Relevant articles and documents
Total Synthesis of Atisane-Type Diterpenoids: Application of Diels-Alder Cycloadditions of Podocarpane-Type Unmasked ortho-Benzoquinones
Song, Liqiang,Zhu, Guili,Liu, Yongjiang,Liu, Bo,Qin, Song
, p. 13706 - 13714 (2015)
Few examples of [4 + 2] cycloaddition with unmasked ortho-benzoquinones (UMOBs) as carbodiene have been reported in complex molecule synthesis. Herein we report that this cycloaddition with podocarpane-type UMOB was developed and applied to construct fully functionalized bicyclo[2.2.2]octanes. Based on this methodology, divergent total syntheses of atisane-type diterpenoids, including (±)-crotobarin, crotogoudin, atisane-3β,16α-diol, and 16S,17-dihydroxy-atisan-3-one, were accomplished in 14, 14, 12, and 16 steps, respectively. Key elements in these total syntheses include: (1) FeCl3-catalyzed cationic cascade cyclization to construct podocarpane-type skeleton; (2) Mn(III)/Co(II)-catalyzed radical hydroxylation of alkene with high regio-, diastereo-, and chemoselectivities; (3) and a ketal-deprotection/lactone-opening/deprotonation/lactonization cascade. Additionally, the synthetic utility of the fully functionalized bicyclo[2.2.2]octane framework was further elucidated by applying ring distortion strategy to afford different skeleton-rearranged natural product-like compounds.
Geraniol grafted chitosan oligosaccharide as a potential antibacterial agent
Yue, Lin,Li, Jingru,Chen, Wanwen,Liu, Xiaoli,Jiang, Qixing,Xia, Wenshui
, p. 356 - 364 (2017)
The novel derivatives of geraniol grafted chitosan oligosaccharide were synthesized via substitution and deprotection reaction, respectively. The products were identified by Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (NMR), X-ray diffraction analysis (XRD), Thermogravimetric analysis (TGA) and UV–vis absorption spectroscopy. It is revealed that the derivatives exhibited a good solubility, thermal stability and antibacterial properties.
(-)-Axinyssene: A novel cytotoxic diterpene from a Japanese marine sponge Axinyssa sp
Kodama, Kota,Higuchi, Ryuichi,Miyamoto, Tomofumi,Van Soest, Rob W. M.
, p. 169 - 171 (2003)
(Matrix presented) A novel diterpene, (-)-axinyssene, was isolated from the Japanese marine sponge Axinyssa sp. The structure of (-)-axinyssene was determined on the basis of spectroscopic and synthetic evidence to be 1-methyl-4-[(4E)-5′9′-dimethyl-1′-methylene-4′, 8′-decadienyl]-(4S)-cyclohexene. (-)- and (+)-axinyssene showed mild cytotoxicity against acute promyelocytic leukemia, HL-60 cells.
Triazole-based inhibitors of geranylgeranyltransferase II
Zhou, Xiang,Hartman, Sara V.,Born, Ella J.,Smits, Jacqueline P.,Holstein, Sarah A.,Wiemer, David F.
, p. 764 - 766 (2013)
A small set of triazole bisphosphonates has been prepared and tested for the ability to inhibit geranylgeranyltransferase II (GGTase II). The compounds were prepared through use of click chemistry to assemble a central triazole that links a polar head group to a hydrophobic tail. The resulting compounds were tested for their ability to inhibit GGTase II in an in vitro enzyme assay and also were tested for cytotoxic activity in an MTT assay with the human myeloma RPMI-8226 cell line. The most potent enzyme inhibitor was the triazole with a geranylgeranyl tail, which suggests that inhibitors that can access the enzyme region that holds the isoprenoid tail will display greater activity.
Design, synthesis, and biological evaluation of novel FXR agonists based on auraptene
Qiu, Qianqian,Wang, Yanjuan,Gu, Guolong,Yu, Fan,Zhang, Shichao,Zhao, Yining,Ling, Bai
, (2021/08/03)
Farnesoid X receptor (FXR) has been considered as an attractive target for metabolic disorder and liver injury, while many current FXR agonists suffer from undesirable side effects, such as pruritus. Therefore, it is urgent to develop new structure types different from current FXR agonists. In this study, a series of structural optimizations were introduced to displace the unstable coumarin and geraniol scaffolds of auraptene (AUR), a novel and safe FXR agonist. All of these efforts led to the identification of compound 14, a potent FXR agonist with nearly fourfold higher activity than AUR. Molecular modeling study suggested that compound 14 fitted well with binding pocket, and formed the key ionic bond with His291 and Arg328. In acetaminophen-induced acute liver injury model, compound 14 exerts better therapeutic effect than that of AUR, which highlighting its pharmacological potential in the treatment of drug-induced liver injury.
New hybrid compounds combining fragments of usnic acid and monoterpenoids for effective tyrosyl-dna phosphodiesterase 1 inhibition
Dyrkheeva, Nadezhda S.,Filimonov, Aleksandr S.,Luzina, Olga A.,Zakharenko, Alexandra L.,Ilina, Ekaterina S.,Malakhova, Anastasia A.,Medvedev, Sergey P.,Reynisson, Jóhannes,Volcho, Konstantin P.,Zakian, Suren M.,Salakhutdinov, Nariman F.,Lavrik, Olga I.
, (2021/07/02)
Usnic acid (UA) is a secondary metabolite of lichens that exhibits a wide range of biological activities. Previously, we found that UA derivatives are effective inhibitors of tyrosyl-DNA phosphodiesterase 1 (TDP1). It can remove covalent complex DNA-topoisomerase 1 (TOP1) stabi-lized by the TOP1 inhibitor topotecan, neutralizing the effect of the drugs. TDP1 removes damage at the 3′ end of DNA caused by other anticancer agents. Thus, TDP1 is a promising therapeutic target for the development of drug combinations with topotecan, as well as other drugs for cancer treatment. Ten new UA enamino derivatives with variation in the terpene fragment and substituent of the UA backbone were synthesized and tested as TDP1 inhibitors. Four compounds, 11a-d, had IC50 values in the 0.23–0.40 μM range. Molecular modelling showed that 11a-d, with relatively short aliphatic chains, fit to the important binding domains. The intrinsic cytotoxicity of 11a-d was tested on two human cell lines. The compounds had low cytotoxicity with CC50 ≥ 60 μM for both cell lines. 11a and 11c had high inhibition efficacy and low cytotoxicity, and they enhanced topotecan’s cyto-toxicity in cancerous HeLa cells but reduced it in the non-cancerous HEK293A cells. This “protec-tive” effect from topotecan on non-cancerous cells requires further investigation.
A mild method for the replacement of a hydroxyl group by halogen: 3. the dichotomous behavior of α-haloenamines towards allylic and propargylic alcohols
Munyemana, Fran?ois,Patiny, Luc,Ghosez, Léon
, (2021/06/07)
A study of the deoxyhalogenation of allylic and propargylic alcohols with tetramethyl-α-halo-enamines is reported. Primary allylic and primary and secondary propargylic alcohols gave the corresponding halides in high yields. Secondary allylic and propargylic alcohols yielded the corresponding secondary halides but the reaction also produced some rearranged primary halides (I > Br > Cl). The reactions with tertiary allylic and tertiary propargylic alcohols gave several products and was therefore of little synthetic value. However, the addition of triethylamine to the reaction mixture or the use of lithium alkoxide instead of alcohol brought about a major change of the course of the reaction which led to amides carrying an allyl or an allenyl group at C2. This was shown to result from a Claisen-Eschenmoser rearrangement of an intermediate α-allyloxy- or propargyloxy-enamine.
