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1.
Artículo en Inglés | IMSEAR | ID: sea-158121

RESUMEN

Simple, accurate and reproducible visible spectrophotometric methods for the assay of drug fluvoxamine as maleate were established based on the formation of oxidative coupling reaction between the corresponding drug, Brucine-NaIO4 and DCQC. The procedures described were applied successfully to the determination of the compound in their dosage forms. The results showed that the proposed procedures compared favorably with the reference methods and satisfactory sensitivity, accuracy and precision. The optical characteristics such as Beer’s law limits, molar absorptivity and sandell’s sensitivity are reported. Regression analysis using the method of least squares was made to evaluate the slope (b), intercept (a) and correlation coefficient (r) and standard error of estimation (Se) for the drug.

2.
Artículo en Chino | WPRIM | ID: wpr-840243

RESUMEN

Objective: To search for new isoflavones with more potent antitumor activities from the target compounds synthesized by inserting a double bond or an acetylene bond between chromone and its 3-substituted phenyl, ester and hydroxymethyl groups, or by formation of an amide of 3′ or 4′-amino group of isoflavones with norcantharidin. Methods: The key intermediate 3-iodo-7-methoxyl-4H-chromen-4-one (5) was prepared with 2-hydroxyl-4-methoxyl- acetophenone and ethyl formate. The target compounds with 3-substituted double bond or acetylene groups were synthesized by Heck coupling and Sonogashira coupling reaction; the amide compounds were synthesized by Suzuki coupling reaction and amide formation of 3′ or 4′-amino group of isoflavones with norcantharidin. All of the target compounds were confirmed by 1HNMR, MS and IR spectra. The IC50 values of target compounds were determined by the standard method using two kinds of human tumor cell lines, colon cancer cell line HCT116 and liver cancer cell line SMMC 7721 to study their anti-tumor activities. Results: All the 17 target compounds obtained had certain anti-tumor effect in vitro, with compounds 7h and 7e showing better anti-tumor effects, which were similar to that of control curcumin and more potent than that of genistein in vitro. Conclusion: The insertion of a double bond or an acetylene bond between chromone and its 3-substituted phenyl, ester and hydroxymethyl groups may promote the anti-tumor activities of isoflavone analogues. It seems that the formation of an amide of 3′- or 4′-amino group of isoflavones with norcantharidin has no noticeable promotion effect on the anti-tumor activities.

3.
Artículo en Coreano | WPRIM | ID: wpr-155610

RESUMEN

PURPOSE: 5-iododeoxyuridine analogues have been exclusively developed for the potential antiviral and antitumor therapeutic agents. In this study, we synthesized carbocyclic radioiododeoxyuridineanalogue (ddIVDU) and carbocyclic intermediate as efficient carbocyclic radiopharmaceuticals. MATERIALS AND METHODS: The synthesis is LAH reduction, hetero Diels-Alder reaction as key reactions including Pd(0)-catalyzed coupling reaction together with organotin. MCA-RH7777 (MCA) and MCA-tk (HSV1-tk positive) cells were treated with various concentration of carbocyclic ddIVDU, and GCV. Cytotoxicity was measured by the MTS methods. For in vitro uptake study, MCA and MCA-tk cells were incubated with 1uCi of [(125)I]carbocyclic ddIVDU. Accumulated radioactivity was measured after various incubation times. RESULTS: The synthesis of ddIVDU and precursor for radioiodination were achieved from cyclopentadiene in good overall yield, respectively. The radioiododemetallation for radiolabeling gave more than 80% yield with > 95% radiochemical purity. GCV was more toxic than carbocyclic ddIVDU in MCA-tk cells. Accumulation of [(125)I]carbocyclic ddIVDU was higher in MCA-tk cells than MCA cells. CONCLUSION: Biological data reveal that ddIVDU is stable in vitro, less toxic than ganciclovir (GCV), and selective in HSV1-tk expressed cells. Thus, this new carbocyclic nucleoside, referred to in this paper as carbocyclic 2',3'-didehydro-2',3'-dideoxy-5- iodovinyluridine (carbocyclic ddIVDU), is a potential imaging probe for HSV1-tk.


Asunto(s)
Reacción de Cicloadición , Ganciclovir , Herpesvirus Humano 1 , Idoxuridina , Radiactividad , Radiofármacos
4.
Artículo en Chino | WPRIM | ID: wpr-539811

RESUMEN

Objective To evaluate the performances of glucose oxidase immobilized on hydrophilic-hydrophobic silica gel, which may be employed to prepare glucose sensor for the determination of glucose in body fluids. Methods The silica gel was prepared from precursors ?-aminopropyltrimethoxysilane (APTMOS) and methyltrimethoxysilane (MTMOS) by sol-gel technique. Glucose oxidase (GOD) was covalently attached to the silica gel via carbodiimide coupling reaction between a carboxylic acid group on enzyme and an amine group of the silica gel under the participation of the linking reagents 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide. The performances of immobilized GOD were explored. Results The optimum conditions were obtained as follows: volume fraction of APTMOS 70%, enzyme content given 16 800 U, the temperature of 35 ℃ and buffer pH 5.5. The decrement in the activity of immobilized GOD for the first 2 weeks was less than 10% of its original activity, and the activity of immobilized GOD retained more than 75% of its original activity after 1 month of testing. Six independently prepared immobilized GOD on the silica gel resulted in an average bioactivity of 1 290.9 ?mol?min -1?g -1 with an R.S.D. of 3.4%. The Michaelis constant (K m) of immobilized GOD was 9.1 mmol?L -1. Conclusion Immobilizing GOD on the silica gel via the formation of peptide bonds is an outstanding enzyme immobilization method.

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