5446-02-6Relevant articles and documents
Highly efficient and chemoselective cleavage of prenyl ethers using ZrCl4/NaBH4
Suresh Babu,China Raju,Srinivas,Madhusudana Rao
, p. 2525 - 2528 (2003)
An efficient and chemoselective deprotection of prenyl ethers of phenols and alcohols with ZrCl4/NaBH4 in DCM was achieved in high yields. The selectivity of prenyl ether deprotection is well demonstrated by carrying out the reaction
Catalytic Carbochlorocarbonylation of Unsaturated Hydrocarbons via C?COCl Bond Cleavage**
Boehm, Philip,Denton, Elliott H.,Fellert, Maximilian,Lee, Yong Ho,Morandi, Bill,Roediger, Sven
supporting information, p. 23435 - 23443 (2021/09/20)
Here we report a palladium-catalysed difunctionalisation of unsaturated C?C bonds with acid chlorides. Formally, the C?COCl bond of an acid chloride is cleaved and added, with complete atom economy, across either strained alkenes or a tethered alkyne to generate new acid chlorides. The transformation does not require exogenous carbon monoxide, operates under mild conditions, shows a good functional group tolerance, and gives the isolated products with excellent stereoselectivity. The intermolecular reaction tolerates both aryl- and alkenyl-substituted acid chlorides and is successful when carboxylic acids are transformed to the acid chloride in situ. The reaction also shows an example of temperature-dependent stereodivergence which, together with plausible mechanistic pathways, is investigated by DFT calculations. Moreover, we show that benzofurans can be formed in an intramolecular variant of the reaction. Finally, derivatisation of the products from the intermolecular reaction provides a highly stereoselective approach for the synthesis of tetrasubstituted cyclopentanes.
Total synthesis of Neocosmosin A
Depa, Manmohan Reddy,Potla, Suneetha,Narkhede, Umesh C.,Jadhav, Vinod D.,Sridhar, Gattu,Vidavalur, Siddaiah
, p. 2817 - 2823 (2021/07/26)
An alternative synthetic route to (?)-Neocosmosin A has been synthesized from commercially available (R)-propylene oxide and 4-Methoxysalicylic acid as starting materials. The key steps involved in the synthesis are alkylation of 1,3-dithiane and Yamaguchi macrolactonization.
Synthesis, structure, and anion binding of functional oxacalix[4]arenes
Ma, Jiao-Xia,Fang, Xu,Xue, Min,Yang, Yong
, p. 5075 - 5085 (2019/06/03)
Oxacalix[4]arenes obtained from the highly efficient, one-pot SNAr reaction were post-macrocyclization functionalized through the reduction of nitro groups and hydrolysis of the ester groups to obtain several derivatives of desired solubility. The difficulties in basic hydrolysis of ester groups were overcome via developing an acid hydrolysis method for tert-butyl ester derivatives of this class. The synthesis of symmetrical oxacalix[4]arenes from an unsymmetrically substituted precursor was also explored via a multiple step fragment coupling approach. Compounds 17 & 18 adopted 1,3-alternate conformations in the solid state as most oxacalix[4]arenes did, and a chair (zigzag) conformation was revealed for tetraamido oxacalix[4]arene (6a) by X-ray single crystal analysis. The tetraureido oxacalixarene (7) showed strong association towards various anions such as F-, Cl-, Br-, I-, Ac-, and HSO4- with a 1:1 stoichiometry as revealed by 1H NMR analysis and UV-vis measurements.
BRARTEMICIN ANALOGUES
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Page/Page column 47-48; 65, (2019/05/22)
The invention relates to brartemicin analogues of Formula (IV) and their uses. These compounds are potent Mincle agonists and Th1-stimulating vaccine adjuvants.
Bavachinin analogues as agonists of pan-peroxisome proliferator-activated receptors
Yi, Jingyu,Du, Guoxin,Zhao, Yuanyuan,Zhang, Liuqiang,Li, Bo,Zhu, Weiliang,Huang, Cheng,Li, Yiming,Guo, Fujiang
, p. 1851 - 1862 (2018/06/18)
Peroxisome proliferator-activated receptors (PPARs) agonists contribute to the regulation of glucose, lipid, and cholesterol metabolism and have emerged as key targets to treat metabolic syndrome. In our previous study, the natural compound bavachinin was found to have pan-PPAR agonist activity. In this study, five isoflavones, three isoflavanones, and five scaffold-hopping analogues of bavachinin were designed, synthesised, and evaluated through reporter gene assays for pan-PPAR agonist activity. The analogue 2-(4-hydroxyphenyl)-6-isopentenyl-7-methoxy-2,3-dihydroquinolin-4(1H)-one (21) was identified as a pan-PPAR agonist, exhibiting substantially higher PPAR α/β agonist activity and equal PPAR-γ agonist activity than does bavachinin.
Gold promoted arylative cyclization of alkynoic acids with arenediazonium salts
Carrillo-Arcos, Ulises A.,Porcel, Susana
supporting information, p. 1837 - 1842 (2018/03/23)
Alkynoic acids derived from salicylic acid and analogues undergo arylative cyclization with arenediazonium salts promoted by gold in the absence of external ligands. The reaction is thermally induced and proceeds even in the absence of light. A difference in regioselectivity has been found compared with that observed in the cycloisomerization process of the same type of compounds.
Lipidated Brartemicin Analogues Are Potent Th1-Stimulating Vaccine Adjuvants
Foster, Amy J.,Nagata, Masahiro,Lu, Xiuyuan,Lynch, Amy T.,Omahdi, Zakaria,Ishikawa, Eri,Yamasaki, Sho,Timmer, Mattie S. M.,Stocker, Bridget L.
, p. 1045 - 1060 (2018/02/17)
Effective Th1-stimulating vaccine adjuvants typically activate antigen presenting cells (APCs) through pattern recognition receptors (PRRs). Macrophage inducible C-type lectin (Mincle) is a PRR expressed on APCs and has been identified as a target for Th1-stimulating adjuvants. Herein, we report on the synthesis and adjuvanticity of rationally designed brartemicin analogues containing long-chain lipids and demonstrate that they are potent Mincle agonists that activate APCs to produce inflammatory cytokines in a Mincle-dependent fashion. Mincle binding, however, does not directly correlate to a functional immune response. Mutation studies indicated that the aromatic residue of lead compound 9a has an important interaction with Mincle Arg183. In vivo assessment of 9a highlighted the capability of this analogue to augment the Th1 response to a model vaccine antigen. Taken together, our results show that lipophilic brartemicin analogues are potent Mincle agonists and that 9a has superior in vivo adjuvant activity compared to TDB.
Synthesis and anti-bacterial activity of a library of 1,2-benzisothiazol-3(2H)-one (BIT) derivatives amenable of crosslinking to polysaccharides
Viani, Fiorenza,Rossi, Bianca,Panzeri, Walter,Merlini, Luca,Martorana, Alessandra M.,Polissi, Alessandra,Galante, Yves M.
, p. 1745 - 1761 (2017/03/08)
1,2-Benzisothiazol-3(2H)-one (BIT) is one of the most common chemical biocides in industrial products, with a heterocyclic structure and a wide range of antimicrobial activity. A library of BIT derivatives was synthesized and characterized, from which 18 compounds were selected, tested for anti-bacterial activity relative to the parent molecule and amenable of coupling to plant polysaccharides in general and to galactomannans (GM) in particular, widely used as rheology modifiers, but with limited “biostability”. Four sites on the BIT core were targeted: the nitrogen and the oxygen atoms on the heterocyclic ring, the C5 and the C6 positions on the aromatic ring, where functional groups were introduced. The ultimate aim of this work is to establish whether by covalently linking a biocide to GM polymers, their “biostability” can be improved.
Rational Design of Rod-Like Liquid Crystals Exhibiting Two Nematic Phases
Mandle, Richard J.,Cowling, Stephen J.,Goodby, John W.
supporting information, p. 14554 - 14562 (2017/10/23)
Recently, a polar, rod-like liquid-crystalline material was reported to exhibit two distinct nematic mesophases (termed N and NX) separated by a weakly first-order transition. Herein, we present our initial studies into the structure–property relationships that underpin the occurrence of the lower-temperature nematic phase, and report several new materials that exhibit this same transformation. We have prepared material with significantly enhanced temperature ranges, allowing us to perform a detailed study of both the upper- and lower-temperature nematic phases by using small-angle X-ray scattering. We observed a continuous change in d spacing rather than a sharp change at the phase transition, a result consistent with a transition between two nematic phases, structures of which are presumably degenerate.
