1.Synthesis of 6beta-[(2'-Aminoethyl)carboxamidomethyl]estradiol and preparation of estradiol probes.
Adamczyk M1, Johnson DD, Reddy RE. Bioconjug Chem. 1998 May-Jun;9(3):403-8.
Reformatsky reaction of 3, 17beta-bis[(2-trimethylsilyl)ethoxymethyl]-1,3, 5(10)-estratrien-6-one (2) with bromoethyl acetate and zinc gave the ester (3) in 60% yield which upon treatment with methanesulfonyl chloride in pyridine afforded the olefinic esters (4 and 5) as an endo and exo mixture (67:33 ratio) in 81% yield. Hydrolysis of the SEM protective groups in compounds 4 and 5 followed by hydrogenation of the resulting hydroxy compounds 6 and 7 using 10% Pd/C afforded an epimeric mixture (beta:alpha = 79:21) of 6-[(ethoxycarbonyl)methyl]estradiol (8a and 8b) in 95% yield. Hydrolysis of the ethyl esters (8a and 8b) using sodium hydroxide gave the acid (9a and 9b) in 81% yield. The epimeric mixture of acids (9a and 9b) was activated, treated with tert-butyl-N-(2-aminoethyl)carbamate (10), and purified by HPLC to afford 6beta-[[[(2-tert-butoxycarbonyl)amino]ethyl]carboxamidomethyl] estradiol (11) in 39% yield as the major isomer. Hydrolysis of the BOC group in compound 11 using TFA afforded the desired 6beta-[(2-aminoethyl)carboxamidomethyl]estradiol 12 in 50% yield.
2.Quantification of luminally released serotonin in rat proximal colon by capillary electrophoresis with laser-induced fluorescence detection.
Qi SD1, Tian SL, Xu HX, Sung JJ, Bian ZX. Anal Bioanal Chem. 2009 Apr;393(8):2059-66. doi: 10.1007/s00216-009-2655-6. Epub 2009 Feb 26.
Serotonin (5-hydroxytryptamine, 5-HT) plays vital roles in regulating gastrointestinal functions. Thus, the detection of 5-HT in the gastrointestinal tract is of great importance for biomedical research, medical diagnosis, and pharmaceutical therapy. This paper presents a simple, sensitive, and fast method for the quantification of luminally released serotonin in the feces and tissues of the rat proximal colon by means of capillary electrophoresis with laser-induced fluorescence detection. 5-Carboxyfluorescein N-succinimidyl ester was used for precolumn derivatization of serotonin. The optimal separation and detection conditions were obtained with an electrophoretic buffer containing 60 mM borate (pH 8.90) and an air-cooled argon-ion laser (excitation at 488 nm, emission at 520 nm). The serotonin concentrations in the feces and tissues of proximal colons were analyzed with this method, and the average values of serotonin in the feces samples were 1.
3.Synthesis of 6 beta-aminoestradiol and its biotin, acridinium, and fluorescein conjugates.
Adamczyk M1, Mattingly PG, Reddy RE. Steroids. 1998 Mar;63(3):130-4.
Amination of 3,17 beta-Bis[(2-trimethylsilylethoxy) methoxy]-1,3,5(10)-estratriene-6-one (2) using NaCNBH4 and NH4OAc afforded 3,17-bis(SEM)-6-aminoestradiol (3) as a mixture of alpha and beta-isomers in 60:40 ratio. Hydrolysis of the mixture of 3 using HF and separation by preparative high-performance liquid chromatography afforded pure 6 beta-aminoestradiol (4) in good yield. The relative stereochemistry of the amino group in 4 was established by NMR. The biotinylated estradiol probe (7), chemiluminescent probe (9), and fluorescent probe (11), were prepared from 6 beta-aminoestradiol (4) and the corresponding biotin, 10-(3-sulfopropyl)-N-tosyl-N-(3-carboxypropyl)acridinium-9-carboxamide, and 5-carboxyfluorescein N-succinimidyl esters in 43-63% yields and > 99% purity.
4.[Study on 5-carboxyfluorescein N-succinimidyl ester in detecting the degree of cross-linked allogenic tissue].
Zahng J1, Liu W, Liu L. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2010 Aug;27(4):816-9.
This study was designed to creat a new method for detecting the degree of cross-linked allogenic tissue based on fluorescent technique. The thoracic aorta of New Zealand rabbits were divided randomly into four groups according to the concentration of Glutaraldehyde (GA), which were group A (control group-with no GA), group B (cross-linked with GA of 0.625%), group C (1.25%), and group D (2.5%). Each group was cross-linked with GA and reacted with 5-FAMSE, and then the fluorescence intensity was observed via fluorescence microscopy (analyzed with Image-Pro Plus 6.0, a professional image analysis software). The differences between groups in order of fluorescence intensity were found to be: group A > roup B > group C > group D (P < 0.01). Meanwhile, the tissue proteins extracted from aorta in each group were submitted to conventional polyacrylamide gel electrophoresis (PGE) after being cross-linked with GA; the result from this method was compared with that from the method of 5-FAMSE.