GENERAL SCIENCE

Scientists stimulate immune system, stop CANCER Growth

Researchers at the University of Illinois at Chicago report that increasing expression of a chemical cytokine called LIGHT in mice with colon cancer activated the immune system's natural cancer-killing T-cells and caused primary tumors and metastatic tumors in the liver to shrink.

LIGHT is an immune-stimulating chemical messenger previously found to have low levels of expression in patients with colon cancer metastases.

Colon cancer is the second-leading cause of cancer-related death in the U.S. and, despite advances in treatment, long-term survival of patients with liver metastases is rare.

"For most patients with colon cancer that has spread to the liver, current treatments are palliative and not curative," says Dr. Ajay Maker, associate professor of surgery in the UIC College of Medicine and corresponding author on the paper. "And while studies have suggested that immunotherapy may be a promising approach for advanced cancers, the use of such treatments for advanced gastrointestinal metastases have not yet been very successful."

Maker, a surgical oncologist, says that this study is exciting because it looks at an immunotherapy intervention for a previously unresponsive gastrointestinal cancer. The intervention, he says, essentially trains the immune system to recognize and attack the tumor, and to protect against additional tumor formation - a significant issue in colon cancer.

Maker and his colleagues established colon cancer tumors in a mouse model, in which the animals had an intact and unedited immune system. Once tumors were sizable, the mice were randomized into two groups - one group had the cytokine LIGHT turned on in the tumors, and the other served as a control group for comparison.

Tumors exposed to LIGHT showed an influx of T-cells that resulted in rapid and sustained diminishment in size, even after expression of the cytokine stopped. In mice with liver metastases, expression of LIGHT similarly provoked a potent immune response that resulted in a significant decrease in tumor burden.

"We demonstrated that delivery of a therapeutic immune-stimulating cytokine caused T-cells to traffic to tumors and to become activated tumor-killing cells," Maker said. "This activity is especially exciting because it resulted in a profound anti-tumor immune response without any other chemotherapy or intervention. The treatment manipulates our natural defenses to fight off the tumor in the same way it has been trained to attack other foreign invaders in our body."

"Not only did we find that LIGHT expression promoted tumor regression, upon further study we also identified the specific type of T-cell - CD8 - that was responsible for shrinking the tumor," Maker said. "These findings are powerful and have great clinical potential."

PHARMANEWS

Phage therapy shown to kill drug-resistant SUPERBUG !!!!

Scientists from the University of Liverpool have shown that phage therapy could offer a safe and effective alternative to antibiotics in the treatment of Cystic Fibrosis lung infections. Chronic lung infections caused by the bacterium Pseudomonas aeruginosa are becoming increasingly difficult to treat due to antimicrobial resistance (AMR). With limited alternative therapeutic options available this has led to a renewed interest in (bacterio)phage therapy.

Phages are viruses that kill bacteria but are otherwise harmless. A major advantage is that phages only target the harmful bacteria, so there are less side of the effects often associated with antibiotics. Phage therapy however has not had the same level of funding as drug development, due to a lack of convincing pre-clinical efficacy studies.

Here for the first time, researchers have shown that phage therapy is highly effective in treating established and recalcitrant chronic respiratory tract infections caused by multi-drug resistant Pseudomonas aeruginosa strains. They show that phages are capable of killing the bacteria in long term infected lungs, such as those suffered by patients with the inherited disease Cystic Fibrosis, indicating a potential new therapeutic option for these hard to treat life threatening infections.

Professor Aras Kadioglu, from the University's Institute of Infection and Global Health, who led the study, said: "Given the increasing problems caused by bacteria that are resistant to treatment with antibiotics, there is an urgent need to develop new approaches. We have shown that phage therapy has the potential to offer a safe and effective alternative for the treatment of such persistent bacterial infections."

Professor Craig Winstanley, who co-led the study, added: "Cystic Fibrosis patients face the prospect of life-long treatment with antibiotics, which often prove ineffective and can have side effects, especially when used for long periods. Hence phage therapy could be a particularly valuable addition to the treatment of chronic lung infections in these patients."

The recent UK Government Review on Antimicrobial Resistance by Jim O'Neil, highlights phage therapy as a potential alternative to antibiotics in the treatment of AMR infections. In addition, the WHO recently identified Pseudomonas aeruginosa as one of the key pathogens against which there is a critical need to develop new therapies. This new study provides valuable pre-clinical evidence for phage therapy being a viable option.

Created by:-Ramashish Kushwaha

FDA Approves Noctiva nasal spray

 The U.S. Food and Drug Administration today approved Noctiva (desmopressin acetate) nasal spray for adults who awaken at least two times per night to urinate due to a condition known as nocturnal polyuria (overproduction of urine during the night). Noctiva is the first FDA-approved treatment for this condition.

“Today’s approval provides adults who overproduce urine at night with the first FDA-approved therapeutic option to help reduce the number of times a night they wake up to urinate,” said Hylton V. Joffe, M.D., M.M.Sc., director of the Division of Bone, Reproductive, and Urologic Products in the FDA’s Center for Drug Evaluation and Research. “It is important to know that Noctiva is not approved for all causes of night-time urination, so patients should discuss their symptoms with their health care provider who can determine the underlying cause of the night-time urination and whether Noctiva is right for them.”

Nocturia (wakening at night to urinate) is a symptom that can be caused by a wide variety of conditions, such as congestive heart failure, poorly controlled diabetes mellitus, medications, or diseases of the bladder or prostate. Before considering Noctiva, health care providers should evaluate each patient for possible causes for the nocturia, and optimize the treatment of underlying conditions that may be contributing to the night-time urination. Because Noctiva is approved only for adults with nocturia caused by nocturnal polyuria, health care providers should confirm overproduction of urine at night with a 24-hour urine collection, if one has not been obtained previously. Health care providers should also be mindful of underlying conditions that can cause nocturia, but that make treatment with Noctiva unsafe, such as excessive drinking of fluids or symptomatic congestive heart failure.

Noctiva is taken daily, approximately 30 minutes before going to bed. It works by increasing the absorption of water through the kidneys, which leads to less urine production.

Noctiva’s efficacy was established in two 12-week, randomized, placebo-controlled trials in 1,045 patients 50 years of age and older with nocturia due to nocturnal polyuria. Although these trials showed a small reduction in the average number of night-time urinations with Noctiva compared to placebo, more patients treated with Noctiva were able to at least halve their number of night-time urinations, and patients treated with Noctiva had more nights with one or fewer night-time urinations.

Noctiva is being approved with a boxed warning and a Medication Guide because it can cause low sodium levels in the blood (hyponatremia). Severe hyponatremia can be life-threatening if it is not promptly diagnosed and treated, leading to seizures, coma, respiratory arrest or death. Health care providers should make sure the patient’s sodium level is normal before starting Noctiva, and should check sodium levels within one week and approximately one month after starting treatment and periodically thereafter. The lower Noctiva dose is recommended as the starting dose for those who may be at risk for hyponatremia, such as the elderly. Noctiva should not be used in patients at increased risk of severe hyponatremia, such as those with excessive fluid intake, those who have illnesses that can cause fluid or electrolyte imbalances, certain patients with kidney damage, and in those using certain medicines, known as loop diuretics or glucocorticoids.

Noctiva should also not be used in patients with symptomatic congestive heart failure or uncontrolled hypertension because fluid retention can worsen these underlying conditions. Use of Noctiva should be discontinued temporarily in patients with certain nasal conditions such as colds or allergies until those conditions have resolved. created by ;- Ramashish Kushwaha

INDIA AMONG TOP 6 GLOBAL PHARMACEUTICAL PRODUCERS

Through the esteemed column of my post , it is to inform u that India is among the top six global pharmaceutical producers in the world. Indian vaccines are exported to 150 countries. India produces 40-70 per cent of the WHO demand for DPT & BCG and 90 per cent of measles vaccine. Approximately 70 per cent of the patients in developing countries receive Indian medicines through NGOs like The Clinton Foundation, Bill & Melinda Gates Foundation, Doctors Without Borders, the UNCTAD etc.

Presently there are 10,500 manufacturing units and over 3,000 pharma companies in India, growing at an exceptional rate. India has about 1,400 WHO GMP approved manufacturing units. India has been accredited with approximately 1,105 CEPs, more than 950 TGA approvals and 584 sites approved by the USFDA. Globally more than 90 per cent of formulations approvals for Anti-retroviral (ARVs), Anti-tubercular & Anti-malarial (WHO pre-qualified) have been granted to India.Manufacturing costs in India are approximately 35-40 per cent of those in the US due to low installation and manufacturing costs. India ranks amongst the top global generic formulation exporters in volume terms.

India's exports of pharma and drugs stood at US$ 16.8 bn.India exports all forms of pharmaceuticals from APIs to formulations, both in modern medicine and traditional Indian medicines.The country's pharmaceutical industry accounts for about 1.4 per cent of the global pharmaceutical industry in value terms and 10 per cent in volume terms.

The Government of India has announced a host of measures to create a facilitating environment for the Indian pharmaceutical industry. The policies of the Government of India are aimed at building more hospitals, boosting local access to healthcare, improving the quality of pharmaceuticals and improving the quality of medical training. The Government of India is committed to setting up robust healthcare and delivery mechanisms. India is well placed to become one of the major drivers in providing healthcare to all while controlling the ever-increasing healthcare spend of both developed and developing nations. Created by -Ramashish kushwaha

NaBH4

                                                      NaBH4
Sodium borohydride is prepared industrially following the original method of Schlesinger: sodium hydride is treated with trimethyl borate at 250–270 °C:

                                B (OCH3)3 + 4 NaH → NaBH4 + 3 NaOCH3

Millions of kilograms are produced annually, far exceeding the production levels of any other hydride reducing agent. Sodium borohydride can also be produced by the action of NaH on powdered borosilicate glass.

Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula NaBH4. This white solid, usually encountered as a powder, is a versatile reducing agent that finds wide application in chemistry, both in the laboratory and on a technical scale. It has been tested as pretreatment for pulping of wood, but is too costly to be commercialized. The compound is soluble in alcohols and certain ethers but reacts with water in the absence of a base.

pharma news

 Researchers identify a new way to promote tissue regeneration

 It is to inform u that science is growing day by day . Now researchers have identified a new way to promote tissue regeneration.Houston Methodist researchers have identified an immune pathway that promotes the formation of a cell that can develop into new tissues and organs. In a new study published in the journal Stem Cells, a team led by John P. Cooke, M.D., Ph.D., chair of Cardiovascular Sciences, Houston Methodist Research Institute, described how activation of innate immunity enhances nuclear reprogramming, one of the first steps in tissue regeneration, or the formation of new tissues and organs from a single cell in the body.

The use of iPSCs to generate tissues would revolutionize transplantation, facilitating the growth of artificial organs. Cellular nuclear reprogramming is a powerful tool that enables researchers to direct a skin cell to become another type of tissue or organ. Cooke's team plans to use the activation of innate immunity to regenerate damaged tissues to improve wound healing or recovery after a heart attack.

This will help the formation of new cell and their ability to regenerate.

If u think that  my post is helpful  or not  , then plz comment like and share @Ramashishkushwaha

PHARMA NEWS

FDA approves first drug for spinal muscular atrophy  !!!

The U.S. Food and Drug Administration has approved Spinraza (nusinersen), the first drug approved to treat children and adults with spinal muscular atrophy (SMA), a rare and often fatal genetic disease affecting muscle strength and movement. Spinraza is an injection administered into the fluid surrounding the spinal cord.

"There has been a long-standing need for a treatment for spinal muscular atrophy, the most common genetic cause of death in infants, and a disease that can affect people at any stage of life," said Billy Dunn, M.D., director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research. "As shown by our suggestion to the sponsor to analyze the results of the study earlier than planned, the FDA is committed to assisting with the development and approval of safe and effective drugs for rare diseases and we worked hard to review this application quickly; we could not be more pleased to have the first approved treatment for this debilitating disease."

The FDA worked closely with the sponsor during development to help design and implement the analysis upon which this approval was based. The efficacy of Spinraza was demonstrated in a clinical trial in 121 patients with infantile-onset SMA who were diagnosed before 6 months of age and who were less than 7 months old at the time of their first dose. Patients were randomized to receive an injection of Spinraza, into the fluid surrounding the spinal cord, or undergo a mock procedure without drug injection (a skin prick). Twice the number of patients received Spinraza compared to those who underwent the mock procedure. The trial assessed the percentage of patients with improvement in motor milestones, such as head control, sitting, ability to kick in supine position, rolling, crawling, standing and walking.

PHARMA NEWS

Drugs similar to Aspirin, Ibuprofen could help treat sepsis, study suggests

A potentially life-saving treatment for sepsis has been under our noses for decades in the non-steroidal anti-inflammatory drugs (NSAIDs) most people have in their medicine cabinets, a new University of Colorado Boulder study suggests. Each year more than 1 million people in the United States contract sepsis, an overwhelming immune response to infection. It kills as many as half of those who contract it, sometimes within days, according to the National Institutes of Health. As the number of cases rises, particularly in intensive care units, pharmaceutical companies have been scrambling to develop a drug to combat the condition.

"NSAIDS like ibuprofen and aspirin are among the most prevalent pharmaceuticals worldwide, with over 30 billion doses taken annually in the United States alone. But their precise mechanisms of action are not entirely understood," said Hang Hubert Yin, a biochemistry professor at CU Boulder's BioFrontiers Institute and lead author of the new paper, published today in Cell Chemical Biology. "We provide the first evidence for a novel mechanism of action for NSAIDS, one we believe could have a direct impact on people's lives."

Researchers have long known that NSAIDs work in part by inhibiting an enzyme called cyclooxygenase (COX). They've also known that these NSAIDs can come with serious side effects. Some NSAIDs have been removed from the market after showing they boosted risk of heart attack and stroke.

Expiry date of pharmaceuticals

It is a legal requirements for all pharmaceutical products must carry the date of manufacture and date of expiry on their label. The period between the two dates is called the 'life period' or Self life' of the drug. Under specified storage conditions ,the product is expected to remain stable (retain >95%) during this period .In India , the schedule P of drugs and cosmetics Act *1940) specifies the life period (mostly 1-5) of drugs and condition of storage.The expiry of the other medicines has to be specified by the manufacture , buy cannot exceed 5yrs , unless permitted by the licensing authority on the basis of the satisfactory stability proof.

Know about NaBH4 ( sodium borohydrate) and its synthesis

Sodium borohydride is prepared industrially following the original method of Schlesinger: sodium hydride is treated with trimethyl borate at 250–270 °C:

                                B (OCH3)3 + 4 NaH → NaBH4 + 3 NaOCH3

Millions of kilograms are produced annually, far exceeding the production levels of any other hydride reducing agent. Sodium borohydride can also be produced by the action of NaH on powdered borosilicate glass.

Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula NaBH4. This white solid, usually encountered as a powder, is a versatile reducing agent that finds wide application in chemistry, both in the laboratory and on a technical scale. It has been tested as pretreatment for pulping of wood, but is too costly to be commercialized. The compound is soluble in alcohols and certain ethers but reacts with water in the absence of a base.

KNOW HOW TO PREPARE LiAlH4

 A small quantity of aluminum chloride (2.7g) was mixed with a 6-fold excess of lithium hydride (4g) under dry nitrogen in a small round bottomed flask, which was then attached through a standard ground glass joint to a vacuum system, and evacuated. About 15 ml of ether was condensed on the reaction mixture at liquid nitrogen temperature. The reaction, which began as the flask was warmed slowly, was allowed to proceed vigorously, but was kept under control by cooling the flask with liquid nitrogen from time to time. The reaction was usually completed in about five minutes. Filtration of the resulting mixture and removal of the solvent from the filtrate as previously described yielded a sample of lithium aluminum hydride adequate for initiation of the reaction of larger batches.

EFFECT OF SURFACE AREA ON RATE OF FILTRATION

FILTERATION- is the separation of solids from a fluid by passing through a porous medium that retains solid but allows the liquid part to pass through.

SLURRY- A suspension to be filtered is known as slurry .

FILTERATE – The clear fluid passing through the filter is the filterate.

FILTER CAKE -  The accumulated solid on the filter are called filter cake.

If the surface area of the filter medium is increased , the rate of filteration will also increase , hence the rate of filteration can be increased by using layer filter.

BEST METHOD 4 PREPARATION OF ASPIRIN

 EXPERIMENTAL PROCEDURE FOR SYNTHESIS OF ASPIRIN

1. PUT ON YOUR CHEMICAL SPLASH-PROOF SAFETY GOGGLES!

2. Adding The Starting Materials

A. Using a weigh boat, weigh out 5.00 g (+ 0.01 g) of salicylic acid (C7H6O3). Transfer this to a 125 mL Erlenmeyer flask using a powder funnel. Record this mass on the Data Sheet.

B. Using the graduated cylinder located under the hood, measure out 7.00 mL of acetic anhydride and add this to the flask. Be sure to do this in the hood and wearing your goggles. Don't let the acetic anhydride contact your skin and don't get the vapors in your eyes.

C. Carefully add 8 drops of concentrated sulfuric acid (18 M H2SO4), a catalyst, to the flask.

3. Heating The Starting Materials

A. At your lab bench, assemble a hot water bath using a 600 or 800 mL beaker and place the flask in the water bath as shown in Figure 1. Make sure that the water bath is located directly under the hood at your lab bench.

B. Place the flask in the water bath and heat. After the water begins to boil, heat for an additional 15 minutes. (NOTE: The hot water bath will be used again later in the procedure.)

 .

4. Cooling The Reaction Mixture

A. After heating, turn the bunsen burner off and CAREFULLY remove the flask from the water bath (remember it is hot!) and allow the flask and contents to cool on the lab bench for about 3 minutes.

B. After the flask has cooled for about 3 minutes, CAUTIOUSLY add 15 mL of room temperature water to the flask to facilitate the decomposition of the excess acetic anhydride. Swirl the flask to mix the contents.

C. Label your flask containing the reaction mixture and place it in an ice bath and cool until the crystallization of the aspirin appears complete (approx. 15 min.). If crystals do not appear, you can scratch the walls of the flask with a stirring rod to induce crystallization.

5. Isolating The Product

A. Collect the solid aspirin using a Buchner funnel and filter paper as shown in Figure 2. Be sure to seat the filter paper in the filter with a small amount of water.

B. Rinse the flask twice with 3 mL of ice cold water to remove any residual crystals.

C. Discard the filtrate left in the filter flask into the waste container under the hood.

6. Recrystallizing The Aspirin

A. Transfer as much of the solid as possible from the Buchner funnel to a clean, dry 250 mL beaker.

B. Add 10 mL of 95% ethanol to the beaker and if necessary, warm (do not boil!) the mixture in the water bath to dissolve the crystals. If the crystals do not all dissolve, add 2 mL more of the ethanol and continue to warm the mixture to dissolve the crystals.

C. When the crystals are all dissolved, add 10 mL of deionized water, cover the beaker with a watch glass, and allow the solution to cool slowly on the lab bench undisturbed for about 10 minutes.

D. After the 10 minutes cooling on the lab bench, complete the crystallization by placing the beaker and contents in the ice bath. (Label your beaker!) Crystals should form. If an "oil" appears instead of a solid, reheat the beaker in the hot water bath until the oil disappears. If crystals do not appear, you can scratch the bottom of the beaker with a stirring rod to induce crystallization.

7. Drying The Purified Aspirin

A. Using a clean circle of filter paper, collect the purified aspirin by suction filtration as before.

B. Dry the crystals by pulling air through them for about 15 minutes. (Discard the filtrate left in the filter flask into the waste container under the hood. Rinse the filter flask with water and discard the rinse water into the waste container under the hood.)

C. Place the aspirin onto a doubled piece of paper towel and set aside to dry while performing the qualitative analysis of the aspirin. (Wash the filter funnel with water and discard the rinse water into the waste container under the hood.)

PREPARATION OF N-PHENYLANTHRANILIC ACID

(A) N-Phenylanthranilic Acid.—In a 1-l. round-bottomed flask fitted with an air-cooled condenser, a mixture of 155 g. (1.66 moles) of aniline, 41 g. (0.26 mole) of o-chlorobenzoic acid (Note 1,, 41 g. (0.3 mole) of technical anhydrous potassium carbonate, and 1 g. of copper oxide is refluxed for two hours, using an oil bath. The excess aniline is removed by distillation with steam (about three hours is required), and 20 g. of decolorizing carbon is added to the brown residual solution. The mixture is boiled for fifteen minutes and filtered by suction. The filtrate is added, with stirring, to a mixture of 30 cc. of concentrated hydrochloric acid and 60 cc. of water. The precipitated acid is filtered with suction when cold. After drying to constant weight in the air, the yield is 46–52 g. (82–93 per cent of the theoretical amount) of a nearly white product; m.p. 179–181° with preliminary shrinking.

(B) Acridone.—In a 500-cc. flask a solution of 42.7 g. (0.2 mole) of N-phenylanthranilic acid  in 100 cc. of concentrated sulfuric acid (sp. gr. 1.84) is heated on a boiling water bath for four hours and then poured into 1 l. of boiling water. Spattering is minimized by allowing the solution to run down the wall of the container. The yellow precipitate is filtered after boiling for five minutes, and the filtrate is saved . The moist solid is boiled for five minutes with a solution of 30 g. (0.28 mole) of sodium carbonate in 400 cc. of water, collected with suction , and washed well with water. After drying in the air the crude acridone weighs 35.5–37.5 g. (91–96 per cent of the theoretical amount) and melts at 344–346° . This material is pure enough for many purposes; it may be recrystallized from a mixture of aniline and acetic acid, using 10 cc. of aniline and 25 cc. of acetic acid for every 2 g. of solid. The recovery is about 90 per cent, and the recrystallized product melts at 348–352° .

PREPARATION OF UROTROPINE

This is the best method of producing urotropine in laboratory :-
1) place formalin (40% solution of formaldehyde ) i  a porcelin dish .
2) add liquid ammonia solution dropwise with stirring.
3)Heat the porcelin dish on the water bath and evaporate the contents with continuous stirring.
4)Remove the solid urotropine from the dish and recrystallise it.

                                PREPARATION OF ACETANILIDE FROM ANILINE

Using a medicine dropper, place 0.15 to 0.20 g of aniline (about 10 drops) (d = 1.02 g/ml) in a

large tared test tube and determine the weight to the nearest mg. Add 5 ml of distilled water to

the test tube and then add 20 drops of acetic anhydride again using a medicine dropper .

stir, the mixture using stirring rod for 5 minutes until solid forms.

The product crystallized in the same test tube. Add 5 ml of water and heat the test tube in a hot water bath ( 400 mL beaker)  with occasional stirring until the entire solid dissolved. Set the test tube aside to cool for 3-5 minutes and then chill it in an ice bath. When crystallization is complete, collect the product by vacuum filtration using a small Büchner funnel . Allow the sample to dry completely. Weigh the dry product, calculate the percentage yield and determine its melting point. Collect to product in a paper and write your name and submit it to your instructor. The aqueous filtrate may be flushed down the drain. 

The procedure illustrated in this experiment involve recrystallization, gravity filtration, suction filtration, melting and mixture melting points, as well as calculations of theoretical and percentage yields. Gravity-filtration utilizes a “fluted” filter paper in the decolorizing or recrystallization step. In gravity filtration, generally the filtrate is the desired material, which is used further in the experiment. In suction filtration, a Büchner funnel is employed to collect the desired crystals resulting from a reaction or recrystallization attempt. Be sure to “wet the filter paper” with the solvent/solid mixture to be filtered. When performing a suction filtration, it is usually advisable to install a trap between the aspirator and the suction flask. In any case always break the vacuum before turning the water off. In this operation, the filtrate or “mother liquor” may be concentrated to obtain a second crop, etc. ( or may be disposed- consult with you instructor). This experiment involves four functional groups common in organic chemistry. The substrate (reactants) are both liquids and one of the products is solid. The reaction of aniline with acetic anhydride is a transformation in which products, acetanilide and acetic acid, are obtained. A solid product is often desirable since it may be recrystallized and a melting point determined. Solids prepared in this manner serve a derivative, whose melting point may be correlated with known values and thus is a means of identification and serves as a test for homogeneity or purity.

preparation of phenylbenzoate by using phenol.

AIM:- To prepare phenylbenzoate by using phenol.

PROCEDURE:-  

·       1)  Dissolve 1g of phenol in 15ml of 10%NaOH solution contained in a strong wide mouthed bottle of about 50ml capacity,

·        2)     Then , add 2mL of benzoylchloride , cork the bottle securely and shake the mixture vigorously for 15min.

·        3)   At th end of ths time ,the reaction should be complete . A solid product obtained although a faint smell of benzoyl chloride persist , owinmg slight occlusion by solid product , absorption by cork.

·         4)  Filter of solid ester , breaking the lumps on fiklter paper with a spatula , then wash thoroughly with water and drain.

·         5)    Recrystallize the crude ester by methylated spirit (95% ethanol).

·          6) For this purpose using quantity of hot solvent approx.. twice the  minimum required for complete solution in order to ensure that phenylbenzoate doesnot separate until the temp. of solution has fallen below the melting point of ester.

·         7)  Filter the hot solvent , if necessary through a funnel preheated by filtration of some boiling solvent . phenybenzoate is obtained as colourless crystals.