Acetic anhydride

at -80℃. Signals of ISH were detected by digoxigenin (DIG) labeled single strand cRNA probes. The DIG-labeled cRNA probes were transcribed in vitro from cDNAs of rat GR (~0.4 kb) and rat SERT (~0.7 kb) in pGEM-3Zf vectors with T7 RNA polymerase and DIG RNA labeling mix (Roche, Branford, CT, USA). The amount of the transcript was estimated by comparison to DIG-labeled control RNA (Roche, Branford, CT, USA) in Dot-blot assays on nylon membranes (Roche, Branford, CT, USA). The ISH protocol is similar to the one from Cold Spring Harbor Laboratory with minor modifications (Javelle et al. 2011). In brief, slides were fixed with 4% (w/v) paraformaldehyde followed by 0.05% (w/v) proteinase K treatment for 5 min at 21oC and acetylation with acetic anhydride. Lipids were extracted by washing through an ethanol series: 50, 70, 95 and 100% (vols). Pre-hybridized sections were incubated with 200 µl hybridization solution per slide containing 200 ng DIG-labeled probes at 55oC overnight. At the next morning, the sections were washed extensively and treated with RNase A, then proceed to block in 4% goat serum for one hour. The anti-DIG-alkaline phosphatase antibody (1:200 dilution, Roche, Branford, CT, USA) was applied to sections at 4oC overnight. The color was developed by NBT/BCIP substrates (Roche, Branford, CT, USA ) with refreshments twice a day for 3~5…

synthesize aspirin from salicylic acid and acetic anhydride. The general theory behind this experiment was to study the synthesis of a drug from organic materials. During the experiment, esterification had occurred between reactants salicylic acid and acetic anhydride. Then, phosphoric acid would catalyze the reaction and water would be added to decompose the remaining acetic anhydride. Through the process of filtration, aspirin crystals were collected and separate from the liquid acetic…

structure of potassium hydrogen bis(acetylsalicylate). Results and Discussion: The purpose of this lab was to synthesize acetylsalicylic acid, otherwise known as aspirin, as purely as possible. This was done by reacting 2.00 g of salicylic acid with 5mL of 0.05 mole of acetic anhydride to create acetylsalicylic acid and acetic acid. During the reaction of salicylic acid and acetic anhydride, sulfuric acid was added to the reaction as a catalysis to speed up the reaction between the…

catalyst, synthesizing an ester (Weldegirma, 2014). The catalyst has to be something that will provide the addition of a proton, such as a Lewis acid, in order to provide a more reactive electrophile and speed up the reaction (Fischer Esterification Fischer-Speier Esterification, 2015). Some possibilities for the catalyst are sulfuric acid, tosic acid, and phosphoric acid (James, 2014). For the experiment, the starting materials are salicylic acid, acetic anhydride, and phosphoric acid. The…

Aspirin is produced from the reaction of Salicylic Acid and Acetic Anhydride. Aspririn is a analgesic and antipyretic. The purpose of this experiment is to produce aspirin and analyzing it for yield. Twenty grams of salicylic acid, molecular weight 138.1g/mol, 5.0 mL of acetic anhydride, molecular weight 102.1g/mol and density 1.08g/mL, and 5 drops of concentrated sulfuric acid were mixed in a 125mL flask. The mixture was heated in a 70°C hot water bath then taken out to cool to room…

In this lab we used one of the most common synthetic medicine, Aspirin. Aspirin is the common name but it can also be known as Acetyl Salicylic Acid. Aspirin came to be because the hard work of scientist who were trying to relieve pain and fight fever without the patient suffering deadly side effects. A breakthrough occurred when a chemist named Felix Hoffman knew that phenolic compounds are corrosive because of the free hydroxyl group located on the benzene ring of salicylic acid. He then…

The goal of this experiment was to perform a synthesis of aspirin/ acetylsalicylic acid from salicylic acid, using a chemical synthesis procedure. The synthesis involved breaking the bond with acetic anhydride, also required heat and a catalyst, phosphoric acid, in order to beak and extract the bond. The solution used water in order to purify the solution in the way of recrystallization. The product was characterized using IR spectroscopy and melting point. The pure aspirin product that was…

Salicylic acid’s hydroxyl group readily reacts with acetyl groups in a process called acetylation. The resulting substitution reaction replaces the hydrogen in salicylic acid’s hydroxyl group with an acetyl group thereby forming an ester functional group. This esterification of salicylic acid produces acetylsalicylic acid, or aspirin. Figures 1 and 2 above show the reagents and products involved in the experiment’s esterification of salicylic acid. With excess acetic anhydride and a…

Identification of Analgesic Drugs by Thin-Layer Chromatography 1 (a) In thin-layer chromatography alumina or silica is used as the adsorbent material. (b) The filter paper is placed inside the beaker during separation to act as an adsorbent medium. (c) The ultraviolet lamp is used after TLC separation to illuminate the TLC sheet. (d) Aspirin, acetaminophen, and caffeine are components of analgesic drugs examined in this experiment. 2 A 6cm by 10cm pre-coated TLC sheet will be obtained. On the…

The purpose of this lab was to synthesize acetanilide and use recrystallization to isolate the acetanilide product from small amounts of impurities, acetic acid. Recrystallization is a very effective way for organic chemists to isolate a solid product from a small amount of impurities but cannot be used for liquids. The crude acetanilide product and the recrystallized acetanilide were compared using melting point determination and the recrystallized product was then classified and checked for…