Asymmetric Synthesis Essay Example | Topics and Well Written Essays - 1000 words

Asymmetric Synthesis - Essay Example Hence, it is undeniably interesting to study the catalytic asymmetric synthesis of cinchona alkaloids , which have also been helpful in man's daily living. This includes its role in the production of food flavorings and medicines for different ailments like malaria. Additionally, the popularity of cinchona alkaloids over the years is also because of its qualifications in the three primary criteria of catalysts, which are as follows: 1) the diversity of reactions that the catalyst can trigger; 2) the accessibility of both enantiomeric antipodes of the catalyst at an affordable cost; and 3) the stability of the catalyst. The research aims to study the catalytic asymmetric synthesis of the popular two pairs of cinchona alkaloids which are enantiomeric in nature: cinchonine and cinchonidine, and; quinine and quinidine. The researcher aims to study the two pairs by isolating them through extraction of the bark of the cinchona tree; a native of tropical regions. Due to their widespread use, all four members are readily available in large quantities from most chemical suppliers. Furthermore, before conducting several experiments for the research, the researcher will gather enough materials documenting the history of cinchona alkaloids. ... erature section of the research, which will include information about cinchona alkaloids from one of the earliest uses of cinchona alkaloids in asymmetric catalysis which was demonstrated by Pracejus in the 1960's to catalyze the asymmetric alcoholysis of ketenes (Pracejus, 1964) to its modern uses. Moreover, the study's related literature will consist of theories proposed about the asymmetric synthesis of cinchona alkaloids by chemists of different ages. One interesting theory which will contribute to the study of the alkaloid's catalytic asymmetric synthesis is that the alcohol is activated via a hydrogen bond with the tertiary amine of benzoylquinine. Addition of the alcohol to the ketene is followed by quenching of the resultant enolate by the chiral ammonium salt. The resultant esters are isolated in up to 76% enantiomeric excess. The research will strive to replicate the experiments conducted to support this theory. Also, with the proliferation of recent publications studying cinchona-ketene systems for asymmetric synthesis (Blake, 2001), the study will investigate different assumptions about the asymmetry in the synthesis of cinchona alkaloids. One of the most noticeable of these recent publications which the researcher intends to focus is Lectka's -halogenation of acid chlorides (Wack, 2001). Lectka stated that the benzoylquinine-ketene system reacts with quinone based electrophilic halogenating reagents to yield activated -halogenated esters with enantioselectivities as high as 99%, and with good yields. The study will try to prove this through catalytic asymmetric fluorination, where cinchona derivatives have already been used, though only stoichiometrically (Muiz, 2001). However, despite the efforts to base certain experiments upon previous studies, the

The Nursing profession Essay Example | Topics and Well Written Essays - 2500 words

The Nursing profession - Essay Example The care should not be confined to the physical aliment but also the psychological and spiritual needs. Thus, patient care should have a patient centered approach considering the patients as still active dignified individuals, who can plan, manage and create some meaning out of their end life situation. Understanding of these facts helps in better nursing care. The patients seem to know better (than the past) about health care and they demand more knowledge on their end of life options today. Most of the patients want to discuss their treatment options and have a Right to refuse as per existing laws in UK. Problems pertaining to 'End-of -life' care and care for the aged are on the rise especially when concepts of euthanasia and physician assisted death are trying to find legitimate positions in the society. The present case study is that of an eighty-year-old Mr.X in a care home in London. He is dependant on the staff for most of his daily activities. He has complaints of constant pa in and it has been becoming increasingly difficult to move this man as his bones have become very contracted although he is being made to sit on his chair as often as possible. He is also encouraged to eat with the other residents in the dinning room in spite of his spine becoming so twisted that eating at the table is difficult. Patient X is a Retired School Master, widowed with 7 children all off whom visit him on a regular basis and although he is confused at times his Religion and faith are very important to him and still attends Mass every day in the care home. He has a medical history of Myocardial infarction, chronic heart failure, pacemaker, Paget's disease, depression and Type 2 diabetes. He is a classic example of an aged individual with multiple complications. Any further development in these complications will result in the patient being shifted to Intensive care with the possible outcome of death. Thus, it is an excellent case of a patient where managing patient care is vital rather than just assessment and interventions. The Nurse care for the case study should be based on Roper Logan and Tierney model of nursing (1980) which is a care model based on activities of daily living. Unlike Virginia Henderson (1966) model, which recognizes 14 activities, Roper model recognizes only 12 activities. This includes, maintaining a safe environment, communication, breathing, eating/drinking, elimination, washing/dressing, thermoregulation, mobility, work/play, sexual expressions, sleep and dying. Three problems in nurse care for Mr.X: 1.Chronic pain: Chronic pain of the bones is an unpleasant sensory and emotional experience in the patients with Paget's disease and Mr.X has been diagnosed with Paget's disease. Pain management in patients with Paget's disease helps in the improvement of quality of the patient care. Understanding pain needs specific communication skills based on perception. This is true because many of the terminally ill patients may not be able to verbally communicate their pain. Chronic pain is a pain, which lasts for more than six months. Chronic pain is further classified based on its etiology as 'non-malignant' and 'malignant pain'. Non - malignant is non-cancer related pain and malignant pain is cancer related. Chronic pain depresses, debilates and affects the quality of life (Cole, 2002) .A study by Green et.al (2002) on chronic pain management has revealed a need for further educational insights of physicians. A recent study