122846-05-3Relevant academic research and scientific papers
A reduction-responsive drug delivery with improved stability: disulfide crosslinked micelles of small amiphiphilic molecules
Li, Man,Ling, Longbing,Xia, Qing,Li, Xinsong
, p. 12757 - 12770 (2021/04/14)
Micelles self-assembled from small amphiphilic molecules are unstable in biological fluids, and thus are poor drug carriers. In contrast, amphiphilic polymer micelles can encapsulate hydrophobic drugs in their core to greatly enhance their aqueous solubility and extend their retention time in blood circulation owing to their hydrophilic shell. However, the major disadvantages of conventional polymer micelles are the heterogeneity of the amphiphilic polymer structure and premature drug leakage. Thus, herein, to address these shortcomings, disulfide crosslinked micelles composed of a small amphiphilic molecule, di-lipoyl-glycerophosphorylcholine (di-LA-PC), were developed as redox-responsive drug carriers. Specifically, di-LA-PC was synthesized and self-assembled to form crosslinked micelles under catalysis by dithiothreitol. The disulfide crosslinked micelles maintained high stability in a simulated physiological environment, but rapidly disassembled under reductive conditions. Furthermore, paclitaxel (PTX), as a model drug, was encapsulated in the core of the crosslinked micelles with a high loading content of 8.13%. Thein vitrorelease studies indicated that over 80% of PTX was released from the micelles in the reductive environment, whereas less than 20% PTX was released without reduction in the 68 h test. Benefiting from their nanoscale characteristics, the PTX-loaded micelles showed efficient cellular internalization and effectively induced the death of cancer cells, as revealed in the MTT, apoptosis and cell cycle tests. Moreover, pharmacokinetic studies demonstrated that the crosslinked micelles prolonged the circulation of the incorporated PTX in the bloodstream and increased its accumulation in the tumor tissueviathe EPR effect. Finally, the PTX-loaded micelles displayed prominentin vivoanti-tumor activity in a 4T1 xenograft tumor model. In summary, the di-LA-PC crosslinked micelle platform possesses excellent stability, high loading capacity and reduction-responsive release profile, which may have applications in the delivery of PTX and other anti-cancer drugs.
ACIDIC HYBRID MONOMERS AND DENTAL MATERIALS BASED THEREON
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Paragraph 0107; 0108; 0109; 0128; 0129; 0130, (2017/10/18)
Acidic monomer according to Formula I: in which A is a linear or branched aliphatic C1-C18-hydrocarbon group, which can be interrupted by one or more —O??, —S—, —CO—O—, —O—CO—NH—, —HN—CO—NH— or —CO—NR1—; R1 is H or a C1-C6 alkyl group; X is absent or is a linear or branched aliphatic C1-C10 hydrocarbon group, which can be interrupted by one or more —O—, —S—, —CO—O—, —O—CO—NH—, —HN—CO—NH— or —CO—NR2—; R2 is H or a C1-C6 alkyl group; PG is a radically polymerizable group, preferably vinyl, allyl, CH2═CR3—CO—Y— or R4O—CO—C(═CH2)—CH2—Y—; Y═O or NR5 or is absent; R3 is H or CH3; R4 is H or a C1-C7 alkyl group; R5 is H or a C1-C7 alkyl group; n is 1, 2, 3 or 4; m=1 or 2; p=1, 2 or 3; and q=1, 2 or 3. The monomers are particularly suitable as components of dental material.
A new method for cleavage of silicon-carbon linkers on glass plate supports with applications to solid-phase syntheses on silica resins
Terauchi, Takeshi,Machida, Sachiko,Komba, Shiro
supporting information; experimental part, p. 1497 - 1499 (2010/04/29)
We describe herein a novel and facile method for the cleavage of a silicon-based linker on solid-phase supports such as glass plates or silica resin. The linker was efficiently cleaved by oxidation of the silicon-carbon bond (Tamao-Kumada oxidation) to re
2-iodoxybenzenesulfonic acid as an extremely active catalyst for the selective oxidation of alcohols to aldehydes, ketones, carboxylic acids, and enones with oxone
Uyanik, Muhammet,Akakura, Matsujiro,Ishihara, Kazuaki
supporting information; experimental part, p. 251 - 262 (2009/06/28)
Electron-donating group-substituted 2-iodoxybenzoic acids (IBXs) such as5-Me-IBX (1g), 5-MeO-IBX (1h), and 4,5-Me2-IBX were superior to IBX 1a as catalysts for the oxidation of alcohols with Oxone (a trad emark of DuPont) under nonaqueous conditions, although Oxone was almost insoluble in most organic solvents. The catalytic oxidation proceeded more rapidly and cleanly in nitromethane. Furthermore, 2-iodoxybenzenesulfonic acid (IBS, 6a) was much more active than modified IBXs. Thus, we established a highly efficient and selective method for the oxidation of primary and secondary alcohols to carbonyl compounds such as aldehydes, carboxylic acids, and ketones with Oxone in nonaqueous nitromethane, acetonitrile, or ethyl acetate in the presence of 0.05-5molpercentof 6a, which was generated in situ from 2-iodobenzenesulfonic acid (7a) or its sodium salt. Cycloalkanones could be further oxidized to α,β- cycloalkenones or lactones by controlling the amounts of Oxone under the same conditions as above. When Oxone was used under nonaqueous conditions, Oxone wastes could be removed by simple filtration. Based on theoretical calculations, we considered that the relatively ionic character of the intramolecular hypervalent iodine-OSO2 bond of IBS might lower the twisting barrier of the alkoxyperiodinane intermediate 16.
Construction of the key amino alcohol moiety of the cinchona alkaloids
Kobayashi, Yuichi,Motoyama, Yuuya
, p. 2670 - 2672 (2008/09/16)
An N-Teoc [CO2(CH2)2TMS] protected form of the amino alcohol moiety found in the cinchona alkaloids was constructed by Curtius rearrangement followed by reaction of the isocyanate intermediate with TMS(CH2)2OH in one pot. Deprotection of the TV-Teoc protective group and subsequent piperidine ring formation were easily accomplished with CsF in DMF at 110 °C in one pot to afford model compounds of the alkaloids. Georg Thieme Verlag Stuttgart.
Catalytic asymmetric synthesis of macrocyclic (E)-allylic alcohols from ω-alkynals via intramolecular 1-alkenylzinc/aldehyde additions
Oppolzer,Radinov,El-Sayed
, p. 4766 - 4770 (2007/10/03)
The ω-alkynals yielded macrocyclic (S)-allylic alcohols in a one-pot reaction sequence involving alkyne monohydroboration, boron to zinc transmetalation, and ((+)-DAIB)-catalyzed enantioselective intramolecular ring closure to the aldehyde function. A general study of this macrocyclization methodology is presented with respect to ligand type, size, and nature of the formed rings.
