Synthesis of new 1 H ‐spiro[acridine‐9,3′‐indoline]‐1,2’( 2 H , 10 H )‐dione derivatives using aqueous ethanol as a reaction medium

Water-insoluble β - ( 1 - 3 ) – D - glucan isolated from the sclerotium of Poria cocos hardly exhibits biological activity. Therefore, it is advantageous to produce a value-added product from Poria cocos. We extracted the β - ( 1 - 3 ) – D - glucan from the sclerotium of Poria cocos and synthesized a carboxymethylated derivative, carboxymethyl-pachyman (CMP). The influences on the degrees of substitution ( DS ) of CMP, for example, volume ratio of ethanol to water, [NaOH]/[MCA] ratio, reaction temperature and reaction time have been examined, respectively. The most favorable conditions for pachyman carboxymethylation are obtained with a [NaOH]/[MCA] ratio of 1.5, at 45°C for 60 minutes with a reaction medium consisting of a ethanol/water 80:20 (v/v) mixture.

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A multicomponent, facile and catalyst-free microwave-assisted protocol for the synthesis of pyrazolo-[3,4-b]-quinolines under green conditions

RSC Advances ◽

10.1039/c9ra04604f ◽

2019 ◽

Vol 9 (53) ◽

pp. 30768-30772 ◽

Cited By ~ 10

Author(s):

Mandlenkosi Robert Khumalo ◽

Surya Narayana Maddila ◽

Suresh Maddila ◽

Sreekantha B. Jonnalagadda

Keyword(s):

Ambient Temperature ◽

Aqueous Ethanol ◽

Reaction Medium ◽

One Pot ◽

Microwave Assisted ◽

Catalyst Free ◽

Green Conditions

A facile, swift and ecofriendly microwave-assisted multi-component/one-pot protocol is designed for the synthesis of novel pyrazolo-[3,4-b]-quinolines at ambient temperature in aqueous ethanol as a reaction medium.

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Studies of the Hydrolysis and Polymerization of Silicon Alkoxides in Basic Alcohol Solutions

MRS Proceedings ◽

10.1557/proc-121-57 ◽

1988 ◽

Vol 121 ◽

Cited By ~ 4

Author(s):

G. H. Bogush ◽

G. L. Dickstein ◽

P. Lee ◽

K.C. ◽

C. F. Zukoski

Keyword(s):

Aqueous Ethanol ◽

Average Particle Size ◽

Reaction Medium ◽

Particle Growth ◽

Ionic Species ◽

Average Particle ◽

Silicon Alkoxides ◽

Long Time ◽

Time Region ◽

Kinetics Of

ABSTRACTWe report here an experimental technqiue based on changes in reaction medium volume which we have used to observe the kinetics of hydolysis and polymerization of TEOS in aqueous ethanol solutions containing NH3. Our results show that there are three distinct reaction regions. By combining these results with determinations of change in reaction medium conductivity and average particle size, we are able to link the short and long time regions to TEOS hydrolysis and particle growth respectively. The intermediate reaction time region is not associated with hydrolysis, loss of ionic species due to condensation or to particle growth.

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Reaction of thioamides with 2,3-dichloro-1,4-naphthoquinone. A novel synthesis of naphtho[2,3-d]thiazole-4,9-diones

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850071 ◽

1985 ◽

Vol 50 (1) ◽

pp. 71-79 ◽

Cited By ~ 15

Author(s):

A. S. Hammam ◽

B. E. Bayoumy

Keyword(s):

Aqueous Ethanol ◽

Reaction Medium ◽

Novel Synthesis

The reaction of thioamide II with 2,3-dichloro-1,4-naphthoquinone (I) in ethanol gave naptho[2,3-d]thiazole-4,9-diones (IV). The intermediates, 2-thioamido-3-chloro-1,4-naphthoquinones III were also isolated from the reaction medium and could be separately transformed to IV by further boiling in aqueous ethanol containing bicarbonate. The reaction of thiosemicarbazide with I under similar conditions gave naphtho[2,3-e]-2-amino-4H-1,3,4-thiadiazine-5,10-dione (VII).

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High-voltage cytochemistry for three-dimensional observation of nuclei and calculation of total numbers of nuclear pores in retinal Mueller glia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016234x ◽

1990 ◽

Vol 48 (3) ◽

pp. 956-957

Author(s):

H. Ishigooka ◽

S. Ueno ◽

L.M. Hjelmeland ◽

M.B. Landers ◽

K. Ogawa

Keyword(s):

Nuclear Envelope ◽

High Voltage ◽

Three Dimensional ◽

Reaction Medium ◽

Nuclear Pores ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

High Voltage Electron ◽

G6pase Activity ◽

Mueller Glia

Introduction: We have demonstrated that Glucose-6-phosphatase (G6Pase) activity is localized to the endoplasmic reticulum and nuclear envelope of Mueller glia in the normal and pathological guinea pig retina. Using a combination of this cytochemical technique and high voltage electron microscopy, the distribution of nuclear pores could be clearly observed on the nuclear envelope of Mueller glia because of their anatomical lack of reaction products. This technique was developed to study the three-dimensional structure of nuclei and to calculate total numbers of nuclear pores utilizing a computer graphic analysis system in the normal and pathological retina.Materials and methods: Normal and photocoagulated retina of pigmented adult guinea pigs were perfused with a cold mixture of 0.25% glutaraldehyde and 2% paraformaldehyde in 0.1M cacodylate buffer, and the enucleated globes were hemisected and immersed in the same fixative for 30 min. After sectioning and incubation in the reaction medium for the detection of G6Pase activity by the method of Wachstein-Meisel, the sections were postfixed, dehydrated and embedded in Spurr’s epoxy resin. Serial thick sections (1.0um) were prepared for the observation by a Hitachi high voltage electron microscope (H 1250-M) with an accelerating voltage of 1000 Kv. and pictures were analyzed and three-dimensionally reconstructed by TRI (RATOC Co., Ltd.).

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Basic hydrolysis of carbamate to amine in aqueous ethanol

ChemSpider Synthetic Pages ◽

10.1039/sp734 ◽

2014 ◽

Author(s):

John MacMillan

Keyword(s):

Aqueous Ethanol ◽

Basic Hydrolysis ◽

Hydrolysis Of

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Reaction of Acetaldehyde with Human Platelets

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648393 ◽

1992 ◽

Vol 67 (01) ◽

pp. 126-130 ◽

Cited By ~ 8

Author(s):

Olivier Spertini ◽

Jacques Hauert ◽

Fedor Bachmann

Keyword(s):

Platelet Aggregation ◽

Inhibitory Action ◽

Ex Vivo ◽

Platelet Rich Plasma ◽

Shape Change ◽

Reaction Medium ◽

Human Platelets ◽

Membrane Glycoproteins ◽

Neutral Ph

SummaryPlatelet function defects observed in chronic alcoholics are not wholly explained by the inhibitory action of ethanol on platelet aggregation; they are not completely reproduced either in vivo by short-term ethanol perfusion into volunteers or in vitro by the addition of ethanol to platelet-rich plasma. As acetaldehyde (AcH) binds to many proteins and impairs cellular activities, we investigated the effect of this early degradation product of ethanol on platelets. AcH formed adducts with human platelets at neutral pH at 37° C which were stable to extensive washing, trichloracetic acid hydrolysis and heating at 100° C, and were not reduced by sodium borohydride. The amount of platelet adducts formed was a function of the incubation time and of the concentration of AcH in the reaction medium. At low AcH concentrations (<0.2 mM), platelet bound AcH was directly proportional to the concentration of AcH in the reaction medium. At higher concentrations (≥0.2 mM), AcH uptake by platelets tended to reach a plateau. The amount of adducts was also proportional to the number of exposures of platelets to pulses of 20 pM AcH.AcH adducts formation severely impaired platelet aggregation and shape change induced by ADP, collagen and thrombin. A positive correlation was established between platelet-bound AcH and inhibition of aggregation.SDS-PAGE analysis of AcH adducts at neutral pH demonstrated the binding of [14C]acetaldehyde to many platelet proteins. AcH adduct formation with membrane glycoproteins, cytoskeleton and enzymes might interfere with several steps of platelet activation and impair platelet aggregation.This in vitro study shows that AcH has a major inhibitory action on platelet aggregation and may account for the prolonged ex vivo inhibition of aggregation observed in chronic alcoholics even in the absence of alcoholemia.

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Asymmetric aza-Diels-Alder reaction of Danishefsky’s diene with imines in a chiral reaction medium

10.3390/ecsoc-10-01378 ◽

2006 ◽

Author(s):

Giang Vo-Thanh ◽

Bruce Pégot ◽

Olivier Van Buu ◽

Didier Gori

Keyword(s):

Reaction Medium ◽

Alder Reaction ◽

Diels Alder ◽

Diels Alder Reaction ◽

Danishefsky's Diene

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Chemical Transformation of Fe, Air & Water to Ammonia: Variation of Reaction Rate with Temperature, Pressure, Alkalinity and Iron

10.26434/chemrxiv.6879671.v1 ◽

2018 ◽

Author(s):

Ping Peng ◽

Fang-Fang Li ◽

Xinye Liu ◽

Jiawen Ren ◽

jessica stuart ◽

...

Keyword(s):

Particle Size ◽

Reaction Rate ◽

Electrolyte Concentration ◽

Iron Concentration ◽

Reaction Medium ◽

Iron Particle ◽

Intermediate Step ◽

Ammonia Production ◽

Pure Nitrogen ◽

Alkaline Reaction

The rate of ammonia production by the chemical oxidation of iron, N2(from air or as pure nitrogen) and water is studied as a function of (1) iron particle size, (2) iron concentration, (3) temperature, (4) pressureand (5) concentration of the alkaline reaction medium. The reaction meduium consists of an aqueous solution of equal molal concentrations of NaOH and KOH (Na0.5K0.5OH). We had previously reported on the chemical reaction of iron and nitrogen in alkaline medium to ammonia as an intermediate step in the electrochemical synthesis of ammonia by a nano-sized iron oxide electrocatlyst. Here, the intermediate chemical reaction step is exclusively explored. The ammonia production rate increases with temperature (from 20 to 250°C), pressure (from 1 atm to 15 atm of air or N2), and exhibits a maximum rate at an electrolyte concentration of 8 molal Na0,5K0,5OH in a sealed N2reactor. 1-3 µm particle size Fe drive the highest observed ammonia production reaction rate. The Fe mass normalized rate of ammonia production increases with decreasing added mass of the Fe reactant reaching a maximum observed rate of 2.2x10-4mole of NH3h-1g-1for the reaction of 0.1 g of 1-3 µm Fe in 200°C 8 molal Na0.5K0.5OH at 15 atm. Under these conditions 5.1 wt% of the iron reacts to form NH3via the reaction N2+ 2Fe + 3H2O ®2NH3+ Fe2O3.

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