A comparative structural study of the steroid epimers: 17 beta-amino-1,3,5(10)-estratrien-3-ol, 17 alpha-amino-1,3,5(10)-estratrien-3-ol, and some derivatives by 1H NMR, and x-ray diffraction analysis

The epimers 17 beta-amino-1,3,5(10)-estratrien-3-ol and 17 alpha-amino-1,3,5(10)-estratrien-3-ol were synthesized. 17 beta-Amino-1,3,5(10)-estratrien-3-ol was prepared by catalytic hydrogenation of the estrone-oxime. The 17 alpha-amino epimer was obtained from estradiol, via tosylate, followed by nucleophilic displacement by sodium azide and subsequent reduction with LiAlH4. They were characterized by spectroscopic methods. Determination of the crystal structures of 3-(toluene-4-sulfonyloxy)-17 alpha-1,3,5(10)-estratriene, 3-(toluene-4-sulfonyloxy)-17-alpha-amino,1,3,5(10)-estratriene hydrochloride, 17 beta-acetylamino-1,3,5(10)-estratriene-3-ol, and 3-acetoxy-17 beta-acetylamino-1,3,5(10)-estratriene enabled us to characterize the structure of the 17 alpha and 17 beta amino epimers for the first time.     

Estrogenic effects of the synthetic aminoestrogen 17 beta-(5-hydroxy-1-pentylamino)-1,3,5(10)-estratrien-3-ol (pentolame)

In this study, we investigated the effects of pentolame, a 17 beta-aminoestrogen derivative, upon coagulation, serum LH, pituitary progestin receptors, uterine weight, and endometrium morphological changes in the castrated female rat. Groups of animals were subcutaneously (s.c.) injected with either estradiol (E2) (0.1 up to 1000 micrograms/animal), pentolame (1 up to 1000 micrograms/animal), or the vehicle alone daily for 5 consecutive days starting 2 weeks following ovariectomy. Administration of pentolame (10 to 1000 micrograms/animal) increased significantly (p < 0.05) the blood clotting time when compared with that obtained in the group of control animals (EC50 582 micrograms). Pentolame (500 and 1000 micrograms/rat for 5 days) caused a significant inhibition (p < 0.01) of serum LH levels (IC50 860 micrograms), which remained suppressed until Day 5 post last injection. In addition, treatment with pentolame was able to restore in the castrated female rat the presence of specific estrogen-dependent progestin binding sites at the anterior pituitary level. The affinity constants and the number of binding sites of pentolame-induced progestin receptors were similar to those obtained with estradiol at equipotent doses (860 micrograms vs. 1 microgram/animal, respectively). Administration of the 17 beta-aminoestrogen derivative resulted in a significant increase in uterine weight (EC50 420 micrograms) and endometrial characteristics were indistinguishable from those observed in the group of rats treated with E2.     

Facile total synthesis and antimicrobial activity of the marine fatty acids (Z)-2-methoxy-5-hexadecenoic acid and (Z)-2-methoxy-6-hexadecenoic acid

The total synthesis of the naturally occurring (Z)-2-methoxy-5-hexadecenoic acid and (Z)-2-methoxy-6-hexadecenoic acid was accomplished using as a key step Mukaiyama's trimethylsilyl cyanide addition to 4- and 5-pentadecenal, respectively. These syntheses further confirm the structures of the natural marine fatty acids and corroborate their cis double-bond stereochemistry. The title compounds were antimicrobial against the Gram-positive bacteria Staphylococcus aureus (MIC 0.35 micromol/mL) and Streptococcus faecalis (MIC 0.35 micromol/mL).     

Inhibitors of sterol synthesis. Chemical synthesis of 7 alpha-ethyl and 16 alpha-ethyl derivatives of delta 8(14)-15-oxygenated sterols and their effects on 3-hydroxy-3-methylglutaryl coenzyme A reductase in CHO-K1 cells

Three-dimensional data representing biological structures can be derived using several methods, including serial section reconstruction, optical sectioning, and tomography. The investigation, comprehension, and communication of structural relationships to others is greatly facilitated by computer-based visualization procedures. We describe SYNU, a suite of programs developed for interactive investigation of three-dimensional structure and for the production of high-quality three-dimensional images and animations. We illustrate the capabilities of SYNU in applications to biological data obtained by confocal light microscopy, serial section, and high-resolution electron microscopy from investigations at the cellular, subcellular, and molecular levels.     

Studies on the pattern of circulating steroids in the normal menstrual cycle. 2. Levels of 20alpha-dihydroprogesterone, 17-hydroxy-progesterone and 17-hydroxypregnenolone and the assessment of their value for ovulation prediction

Plasma levels of 20alpha-dihydroprogesterone, 17-hydroxyprogesterone and 17-hydroxypregnenolone were assayed daily in 15 normally menstruating women during a complete menstrual cycle. In order to ascertain the normalcy of the cycles studied, LH, progesterone and oestradiol were also determined daily. The pattern of 20alpha-dihydroprogesterone was very similar to that of progesterone. The levels found during the proliferative phase (around 240 pg/ml) increased significantly on the day of the LH-surge and reached values of approximately 3.7 ng/ml at the peak period of luteal activity. The plasma levels of 17-hydroxyprogesterone in the proliferative phase were around 380 pg/ml. The first significant increase occurred one day before the LH-surge and was followed by a sharp peak (approximately 1.5 ng/ml) which coincided with the LH peak. A significant decrease occurred after this peak, which reached a nadir two days after the LH-surge. This was followed by a second rise with a rather broad peak (about 1.8 ng/ml) around the 5th to 7th days after the LH-surge. The levels of 17-hydroxypregnenolone did not show any cyclic variation: from all figures a geometric mean value of 1.62 ng/ml was calulated with tolerance limits at 0.241 and 10.8 ng/ml. Individual day-to-day changes in steroid levels were assessed with regard to their potential for the early identification of the day of the LH-surge. A 17-hydroxyprogesterone value of 1.0 ng/ml, or more, was seen for the first time in the cycle on the day of the LH peak in 13 cycles and a progesterone + 17-hydroxyprogesterone level of at least 1.8 ng/ml in 14 of the 15 cycles studies. These data seem to warrant a study of the predictive value of progesterone and 17-hydroxyprogesterone assays in a much larger population.     

新试剂1-(4-安替比林)-3-(对苯甲酸)-三氮烯的合成及其应用研究

以4-氨基安替比林和对氨基苯甲酸为原料,经重氮化和偶联两步反应合成了一个新的三氮烯类显色剂:1-(4-安替比林)-3-(对苯甲酸)-三氮烯(ABTA),并用红外光谱和元素分析对其结构进行了表征.同时,研究了新试剂与Pd(Ⅱ)的显色反应条件,建立了一个测定钯的光度分析新方法.在最佳实验条件下,Pd(Ⅱ)的质量浓度在0.25～2.8μg/ml范围内符合比尔定律, 其摩尔吸光系数ε=2.87×104 L/(mol·cm),大量常见离子对Pd(Ⅱ)的测定不干扰.该方法用于催化剂样品中钯的测定,结果令人满意.     

Studies on the reductive amination of 3-deoxy-D-manno-octulosonic acid (Kdo)

Reductive amination of 3-deoxy-D-manno-octulosonic acid (Kdo) with allylamine (AIIN) or 2-(4-aminophenyl)ethylamine (APEA) yields epimer pairs of 2-N-allylamino and 2-N-[2-(4-aminophenyl)ethylamino]-2,3-dideoxy-D-glycero-D-galacto- and -2,3-dideoxy-D-glycero-D-talo-octonic acid. The yields were 50-60% due to reduction of Kdo to the respective polyols as side reaction products. Mass spectrometric analyses proved the amination derivatives to be the expected glycamines. Nuclear magnetic resonance (NMR) studies were performed on 2-N-allylamino-2,3-dideoxyoctonic acid which represents the chain terminus of allylaminated oligosaccharides derived from bacterial lipopolysaccharides (LPS) after acid hydrolysis and reductive allylamination.     

One-step synthesis and structural quantitative analysis of La_(2/3)Sr_(1/3)MnO_3/La_(1.4)Sr_(1.6)Mn_2O_7 composites

La2/3Sr1/3MnO3/La1.4Sr1.6Mn2O7 composites with arbitrary weight percentage were prepared using a one-step solid-state reaction method. The experimental results demonstrated that addition of K2CO3 during preparation favored the formation of the composites even though the K+ ions were volatilized under the high temperatures of sintering. Full quantitative analysis with the Rietveld method showed that the content of La1.4Sr1.6Mn2O7 phase decreased and the fraction of the La2/3Sr1/3MnO3 phase increased as the a...     

Studies on organosulfur compounds. XV. Substituent effects on 2-(2-pyridyl)-3-substituted-phenyl-4(3H)-quinazolinone cyclization (author''s transl)

The recovery process of HeLa continuous cells after prolonged storage at nitrogen liquid temperature (--196 degrees C) has been analysed. The karyologic analysis evidence indicates a high stock cell karyostability. A study of cell division, generation cycle parameters and DNA synthesis by autoradiography demonstrated cell adaptation to a continuous passage to be due to the increase of proliferative pool and to the intensitification of generation processes in the multiplicated population. Cell structure changes during adaptation were reversible.     

Arsenic metabolism. (17) Studies of placental transfer of arsenic and the effects of antidotes and diet

Albino rats of Wistar strain (Tamura 1950) breeded in a closed colony were administered arsenic trioxide orally during pregnancy (from the 0 day to the 20th day). Organs of fetuses and mother rats were exenterated on the 21st day of gestation and the contents of arsenic measured using an arsenic analyzer unit with atomic absorption spectrophotometry. Whole organs of the fetus were separated into 3 groupings i.e. liver, brain and remaining organs. The contents of arsenic in the organs in each of these groupings and in the placenta were measured. Even in the non-administered group, arsenic was detected in the every organ. In the arsenic administered group, the content of arsenic in the placenta was the highest among the four preparations tested; and the content in the liver and remaining organs was considerably high, but was low in the brain. The level of accumulation of arsenic differed between each organ. In the placenta, the accumulation reached a plateau, and in the brain this accumulation was below one-tenth that in the liver. In the non-administered group, arsenic was detected in the liver, kidney, spleen and brain of mother rats. In the group on arsenite, the content in the kidney and spleen was large, followed by a large amount in the liver and in the brain respectively. The level of accumulation of arsenic in mother rats differed between each organ. Arsenite was administered with antidotes such as dimercaprol, thioctic acid and L-ascorbic acid during pregnancy (from the 0 day to the 5th day). In this group the content of arsenic in the remaining organs was statistically less than that of the control group. The content in the brain was slightly reduced by a co-administration of the antidotes, however, there was no statistical difference in the placenta and liver between the antidote-treated and control groups. The content of arsenic in the kidney of mother rats treated with antidotes was statistically less than that of the controls. Whether or not the content of arsenic in organs of fetuses and mother rats was affected by a milk diet was also studied. The content of arsenic in the organs of fetuses showed no statistical difference between the animals on an Oriental stock diet group and those on the milk diet. On the other hand, the content of arsenic in the kidney of mother rats on the milk diet was statistically less than seen in those in the Oriental stock diet group.