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Dis- the four elements of liability that must cuss with this administrator what you perceive be present to prove that negligence has to be your legal responsibilities to patients in occurred (duty buy shuddha guggulu 60 caps lowest price, breach of duty purchase generic shuddha guggulu canada, causation shuddha guggulu 60caps low cost, terms of patient safety, informed consent, damages): equipment use, incident reports, and medica- tion errors. Think about how you would respond in the brain tumor who is admitted to the pediatric following situation, and discuss your responsi- oncology unit for a pain management program. Are there ever One morning she comes out to the nurses’ sta- differences between the legally prudent and tion and ﬁrmly says, “I’m very unhappy with morally right response? She currently in charge of the boy’s care is under is terriﬁed of your nurse supervisor and has investigation for malpractice in another case. How might the nurses involved in this you that the evening nurses are mean and scenario respond to Ms. Bedford’s disclosure sometimes push and hit her, but she begs that she will be pressing charges against the you not to tell anyone. You observe a surgeon contaminate a sterile ﬁeld; when you inform him, he tells you not to be so squeamish. What intellectual, technical, interpersonal, gon you hear and see if you can deﬁne it. Note and/or ethical/legal competencies are most whether the jury delivers the same verdict that likely to be used in this situation? Describe your reaction to the proceedings and verdict, and state how your conscience would dictate your resolution of the conﬂict. What resources might be helpful for the nurses person take a turn suggesting a legal issue. Interview someone in the legal department of the institution where you will be practicing. Ask them about the legal issues that face Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Diagnosis-related groups were implemented Circle the letter that corresponds to the best by the federal government to meet what answer for each question. Increasing numbers of ill elderly plans is the patient most limited in choice of b. Strong communication and counseling services at a lower fee in return for prompt skills payment and volume guarantee? Aggressive therapy for cancer to care for themselves, and then have access to progressively more healthcare services, as 7. Which of the following patients would be vide physical care but are unable to admin- covered by Medicare? The importance of home healthcare is evi- denced by the growing number of older b. Home healthcare agencies provide many older different health-related services, including 10. Which of the following statements describes nursing assessment, teaching and support a characteristic of case management? Nurses who are case managers give direct growing areas of the healthcare system, care to patients. Medicare is a federally funded public assis- Multiple Response Questions tance program for people of any age who have low incomes. Which of the following are methods used to through a group of afﬁliated providers. Private insurance is always ﬁnanced care as a patient moves through the healthcare through for-proﬁt organizations. Which of the following would be a typical role tend to be higher than those for managed of a nurse in a primary care center? Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. A(n) is a person who enters a institution healthcare facility and stays there for more than 24 hours. Community health nursing practice that and are often open at times other than emphasizes holistic healthcare, health traditional ofﬁce hours. A(n) is a member of the collabo- tion and for treatment of chemical rative team trained in techniques that improve dependency pulmonary function and oxygenation. Provide 24-hour services and hot lines for people who are suicidal, who are abusing e. Rural health centers who required surgery or complicated treatments, or who were having babies m. Primary care centers illnesses, minor surgical procedures, Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. The type of care provided to homebound physician ill, disabled, or elderly patients to allow the primary caregiver to have some time 23. Seeks to restore function or prevent away from the responsibilities of day-to- further disability in a patient after an day care injury or illness 14. Counsels patients and family members major source of health assessment, and informs them of, and refers them health education, and emergency care to, various community resources for the nation’s children. Responsible for the diagnosis of illness system affected the role of the hospital as a and medical or surgical treatment of provider of healthcare services? Help nurses provide direct care to patients; titles include nursing assistants, orderlies, attendants, or technicians 4. Study Guide for Fundamentals of Nursing: The Art and Science of Nursing Care, 7th Edition. Deﬁne the term fragmentation of care and its the help from the home care agency has been effect on the healthcare system: a blessing, but I need more help and some other equipment now, and our insurance com- pany doesn’t cover these things. Plus, now the doctor says that his condition has really wors- ened and he probably has 6 months or less to live. Ritchie appears overwhelmed with her home situation and may be suffering from “caregiver burnout. Think about a group of individuals in your community that is underserved and lacks access to nursing resources. What would be a successful outcome for this and the backgrounds of the patients seeking patient?
Echinacea ginkgo extract did not improve cognitive function quality 60 caps shuddha guggulu, may have is currently most widely used in attempts to prevent the com- contributed to a decline of ginkgo from the top-selling pos- mon cold and influenza symptoms purchase shuddha guggulu 60 caps overnight delivery, but is also used for Candida ition it had held among such products since 1995 buy shuddha guggulu 60 caps otc. One of the infections, chronic respiratory infections, prostatitis and rheuma- principal components of ginkgo, ginkgolide B, is a moderately toid arthritis. Well-controlled studies have shown little, if any, potent antagonist of platelet-activating factor. One recent placebo-controlled study of echinacea in the effects claimed for ginkgo products are postulated to be due to treatment of the common cold actually suggested echinacea did monamine oxidase inhibition by ginkgolides. Adverse effects Serious or fatal side effects of gingko include spontaneous Adverse effects bleeding, fatal intracerebral bleeding, seizures and anaphyl- Adverse effects of echinacea use involve rashes, including actic shock. Less serious side effects are nausea, vomiting, flat- erythema multiforme, arthralgias, allergic reactions, gastro- ulence, diarrhoea, headaches and pruritus. Drug interactions In vitro data suggest ginkgo can inhibit hepatic drug metab- Drug interactions olizing enzymes. In another study, depending on their structures, concentrations and assay con- however, ginkgo increased the plasma concentrations of the ditions. The oral bioavailability of in the phenotyping studies is possibly related to the highly midazolam in this study was significantly increased from 24 variable phytochemical composition of commercially available to 36% in the presence of echinacea, indicating that the hepatic ginkgo extracts. Collectively, these clinical data at the hepatic and intestinal sites and the route of administra- indicate that ginkgo may interfere with the pharmacokinetics tion. It is prudent to discourage soy-derived products in plant native to Europe, North America and western Asia, is patients with oestrogen-dependent tumours (e. Currently, St John’s wort is still widely used Furthermore, as genistein can negate the inhibitory effect of for the treatment of mild to moderate depression and other tamoxifen on breast cancer growth, women taking this agent nervous conditions. Acute vasodilatation caused by varying results of therapy with St John’s wort for depressive 17β-oestradiol is mediated by nitric oxide, and genistein and mood disorders. More recently, a randomized, double- the possibility of beneficial vascular effects. These include catechin-type tannins and condensed-type proanthocyanidins, flavonoids (mostly Drug interactions hyperoside, rutin, quercetin and kaempferol), biflavonoids Isoflavones, such as genistein and daidzein, also inhibit oxida- (e. Given that these trans- porters are involved in the intestinal absorption and biliary secre- tion of many drugs, it is reasonable to suspect that soy may alter drug absorption and/or disposition of such agents in humans. The main constituents of saw palmetto include carbohydrates, fixed oils, steroids, flavonoids, resin, tannin and volatile oil. Saw palmetto is used in men with the hope of ‘toning and strengthening the reproductive system, and specifically for symptoms of prostate enlargement’. In women, the principal use of saw palmetto is to (hopefully) reduce ovarian enlargement and to increase the size of small breasts. Although no drug interactions with, or medical contraindications to, the use of saw palmetto have been reported, it would be prudent to avoid concomitant use with other hormonal therapies, especially oestrogens, and in patients with oestrogen-dependent cancers. Adverse effects The adverse effects of saw palmetto involve gastro-intestinal Figure 17. Chondroitin inhibits the enzymes the putative antidepressant effects of St John’s wort, the phar- that degrade cartilage. Drug controlled, double-blind study evaluated the effects of glu- interactions with therapeutic failure of concomitant drugs, cosamine on disease progression and supported the use of e. Adverse effects Drug interactions The adverse effects associated with glucosamine involve Many clinical trials are now reporting significant pharmacoki- gastro-intestinal disturbances, including dyspepsia, nausea, netic interactions with long-term treatment with St John’s constipation and diarrhoea, skin rashes and allergic reactions wort and drugs from a variety of therapeutic classes. More recently, kava kava (hepatotoxicity), aristocholic acid (nephrotoxicity) it was shown that St John’s wort enhanced the activity of tran- and phen phen (pulmonary hypertension) have recently scription factors, including the pregnane X receptor to tran- been communicated to prescribers and the public. Glucosamine is available as a non-prescription dietary supple- • The most commonly used products are garlic, ginkgo ment and in many products is obtained from shellfish. It is one biloba, echinacea, soy, saw palmetto, ginseng and St of several naturally occurring 6-carbon amino sugars found in John’s wort. Amino sugars are essential building blocks for • The efficacy of such products in many cases is not supported by rigorous clinical trials. Some • Patients believe herbals are safe and are unaware of commercial products contain glucosamine in combination documented or potential toxicities. The precise mechanism of action of glu- • Many patients take herbal products in conjunction with cosamine is unknown. In vitro data suggest glucosamine can prescription medications, unknowingly risking stimulate cartilage cells to synthesize glycosaminoglycans and herb–drug interactions. It is more likely that the cell produces smaller, her drug therapy (either therapeutic failure or toxicity) soluble subunits; assembly of these smaller, soluble subunits a careful history concerning the use of herbal products outside of the cell into a soluble form of collagen has been should be obtained. Nutraceutical therapies tacrolimus, mycophenolic acid and relatively low doses of for degenerative joint diseases: a critical review. When seen in follow up at approximately nine months meta-analysis of randomised controlled trials. Current concepts in Current clinical examination revealed some mild subcostal the therapeutic management of osteoarthritis with glucosamine. British Journal of Clinical laboratory investigation revealed no infectious cause. St John’s wort-associated drug interactions: short- pressive regimen that could lead to this clinical situation? Answer 2 It is possible, but should be clarified with the patient, that she has been taking St John’s wort for anxiety and insom- nia. The current public view of St John’s wort is that it is a harmless, herbal therapy that can be used to help patients with anxiety, insomnia and depression. Carefully enquiring about this possibility with the patient would be mandatory in this case. Apart from rifampicin, other drugs that induce 3A4 (but which the patient has not been prescribed) include phenobarbitone, carbamazepine, other rifamycins, pioglitazone, nevirapine (see Chapter 13). In this associated with troubled dreams punctuated by repeated wak- chapter, we discuss the management – both non-pharmacological enings. The result is that both patient and doctor are tempted to restart medication to suppress the withdrawal phenomena, resulting in a vicious cycle. These include: edly occurs in 35% of adults and is most frequent in women • pain (e. Yes No No Yes Treat underlying Treat underlying cause (Physical/ cause (Physical/ Psychological) Psychological) Chronic/ Chronic/ long-term long-term cause? Yes No No Yes Non-pharmacological Non-pharmacological methods/ methods/ behavioural behavioural therapies therapies No No Severe Severe and/or and/or disabling?
Inferior concha and vomer 1 Ethmoidal process 2 Anterior part of concha 3 Inferior border 4 Ala of vomer 5 Posterior border of nasal septum 6 Lacrimal process 7 Posterior part of concha 8 Maxillary process Right inferior nasal concha (medial aspect) cheap shuddha guggulu 60caps amex. Septum and Cartilages of the Nose 49 1 Crista galli 2 Cribriform plate of ethmoidal bone 3 Perpendicular plate of ethmoidal bone 4 Vomer 5 Ala of the vomer 6 Palatine bone (perpendicular process) 7 Palatine bone (horizontal plate) 8 Mandible 9 Nasal bone 10 Sphenoidal sinus 11 Hypophysial fossa (sella turcica) 12 Grooves for the middle meningeal artery Cartilages of the nose 13 Lateral nasal cartilage 14 Greater alar cartilage 15 Lesser alar cartilages 16 Septal cartilage 17 Location of nasal bone Paramedian sagittal section through the skull including the nasal septum order shuddha guggulu 60caps without prescription. The developing crowns of the permanent teeth are displayed in their crypts in the maxilla and mandible cheap shuddha guggulu online amex. Notice that the breadth of the alveolar arch of the child’s mandible and maxilla holding the deciduous teeth is nearly the same as the comparable portion in the jaws of the adult. Isolated teeth of the alveolar part of the maxilla (top row) and the mandible (lower row), labial surface of the teeth. Temporomandibular Joint and Masticatory Muscles 55 1 2 3 4 5 6 7 8 9 Muscles of mastication and temporomandibular joint. Masticatory Muscles: Pterygoid Muscles 57 1 2 3 4 5 6 7 8 9 10 11 Muscles of mastication. The zygomatic arch and part of the mandible have been removed to reveal the medial and lateral pterygoid muscles. Radially arranged muscles work as Left side: superficial layer, right side: deeper layer. Maxillary Artery 63 1 Galea aponeurotica 2 Superficial temporal artery and auriculo- temporal nerve 3 Occipital artery and greater occipital 1 12 nerve (C2) 4 Temporomandibular joint (opened) 5 External carotid artery 13 6 Mandible and inferior mandibular artery and 2 nerve 14 7 Accessory nerve (Var. I) pass the lamina cribrosa innervating the upper part of the nasal mucous membrane. Brain, brain stem, of the neck, the tongue, and the and cerebellum have been partly removed (from Lütjen-Drecoll, Rohen, Innenansichten des pharynx. V) Brain and Cranial Nerves 67 Brain stem and pharynx with cranial nerves (posterior aspect). Lateral wall of cranial cavity, lateral wall of orbit, zygomatic arch, and ramus of the mandible have been removed and the mandibular canal opened. V2) 2 Supra-orbital nerve pterygopalatine nerves 24 Trigeminal ganglion 3 Lacrimal nerve 13 Posterior superior alveolar 25 Mandibular nerve (n. V3) 4 Lacrimal gland nerves 26 Auriculotemporal nerve 5 Eyeball 14 Superior dental plexus 27 External acoustic meatus (divided) 6 Optic nerve and short ciliary nerves 15 Buccinator muscle and buccal nerve 28 Lingual nerve and chorda tympani 7 External nasal branch of 16 Inferior dental plexus 29 Mylohyoid nerve anterior ethmoidal nerve 17 Mental foramen and mental nerve 30 Medial pterygoid muscle 8 Ciliary ganglion 18 Anterior belly of digastric muscle 31 Inferior alveolar nerve 9 Zygomatic nerve 19 Ophthalmic nerve (n. V1) 32 Posterior belly of digastric muscle 10 Infra-orbital nerve 20 Oculomotor nerve (n. V3) 12 Posterior superior alveolar nerves 13 Tympanic cavity, external acoustic meatus, and tympanic membrane 14 Inferior alveolar nerve 15 Lingual nerve 16 Facial nerve (n. Facial canal and tympanic cavity opened, posterior wall of external acoustic meatus removed. Branches of facial nerve: a = temporal branch; b = zygomatic branches; c = buccal branches; d = marginal mandibular branch. The mandible has been divided and the muscles of mastication have been Facial nerve (schematic drawing of the dissection above). Brain and Cranial Nerves: Connection with the Brain Stem 71 1 1414 2 3 15 16 4 17 5 18 6 19 20 7 8 21 22 9 10 23 24 11 25 26 27 12 28 13 18 29 1 Optic tract 11 Lingual branch of hypoglossal nerve 22 Hypoglossal nerve (n. V) 27 Sympathetic trunk 7 Lingual nerve and inferior alveolar nerve 17 Fourth ventricle and rhomboid fossa 28 Branch of cervical plexus (ventral 8 Styloid process and stylohyoid muscle 18 Vagus nerve (n. V3) 7 23 26 External acoustic meatus 8 21 27 Pterygopalatine nerves 24 28 Deep temporal nerves 10 25 29 Buccal nerve 30 Masseteric nerve 11 31 Auriculotemporal nerve 32 Trochlea and superior oblique muscle 16 Cranial nerves innervating extra-ocular muscles (lateral aspect). Right side: superficial layer, left side: middle layer of the orbit (superior rectus muscle and frontal nerve divided and reflected). V1) 19 Optic chiasma and internal carotid artery 20 Trigeminal ganglion 21 Trigeminal nerve (n. V) 22 Tentorial notch 23 Superior rectus muscle Cranial nerves within the orbit (superior aspect). V) 11 Cerebellum 12 Eyeball 13 Medial and lateral rectus muscles 14 Internal carotid artery 15 Oculomotor nerve (n. Brain and Cranial Nerves: Base of the Skull with Cranial Nerves 75 Base of the skull with cranial nerves (internal aspect). Incision on the right tentorium cerebelli to display the cranial nerves of the infratentorial space. Regions of the Head: Lateral Region 77 1 Temporoparietalis muscle 2 Superficial temporal artery and vein, and auriculotemporal nerve 2 3 Occipital belly of occipitofrontalis muscle and greater occipital nerve (C2) 27 4 Facial nerve (n. Retromandibular and submandibular regions of the head 31 Anterior belly of digastric (lateral aspect). The parotid plexus (4) is formed by anastomosis of the temporal, zygomatic, buccal, marginal mandibular, and cervical branches of the facial nerve, arising in the parotid gland. Masseter muscle and temporal fascia have been partly removed to display the masseteric artery and nerve. The coronoid process together with the insertions of temporalis muscle have been removed to display the maxillary artery. The location of 16 Parotid duct (divided) and buccinator muscle inferior alveolar nerve and artery is indicated by a needle. The great sensory organs are located within the orbit (eye), the nasal cavity (olfactory system), and the petrous portion of the temporal 7 bone (vestibulocochlear organ). The dura mater is firmly attached to the skull and provides shelter and 8 stabilization for the brain. Interposed 9 between pia and dura mater lies the arachnoid containing the cerebrospinal 4 fluid. The eye with the optic nerve is located within the orbit; the labyrinth organ, within the petrous bone. Scalp and Meninges 85 1 Skin 1 2 Galea aponeurotica 2 3 Skull diploe 3 4 Dura mater 5 Arachnoid and pia mater 4 with cerebral vessels 6 Frontal belly of occipitofrontalis 5 muscle 7 Branch of middle meningeal artery 6 8 Pericranium (periosteum) 7 13 9 Lateral and medial branches of 8 supra-orbital nerve 9 10 Orbicularis oculi muscle 11 Zygomatico-orbital artery 14 12 Auriculotemporal nerve and 15 superficial temporal artery and vein 10 13 Superior auricular muscle 11 16 14 Occipital belly of occipitofrontalis muscle 12 17 15 Occipital nerve 16 Occipital artery and vein 17 Greater occipital nerve 18 18 Sternocleidomastoid muscle 19 Frontal lobe 20 Chiasmatic cistern Lateral aspect of the head. Scalp, vertex of the skull, and meninges are demonstrated 21 Interpeduncular cistern by a series of window-like openings. Green = cisterns; blue = dural sinus and ventricles; The subarachnoid space (23) is shown. Meninges: Pia Mater and Arachnoid 89 1 Calvaria and skin of the scalp 2 Dura mater (divided) 3 Position of lateral sulcus 4 Frontal lobe covered by arachnoid and pia mater 5 Frontal sinus 6 Olfactory bulb 7 Sphenoidal sinus 8 Dura mater on clivus and basilar artery 9 Atlas (anterior arch, divided) 10 Soft palate 11 Tongue 12 Epiglottis 13 Vocal fold 14 Position of central sulcus 15 Superior cerebral veins 16 Tentorium (divided) 17 Cerebellum 18 Cerebellomedullary cistern 19 Position of foramen magnum and spinal cord 20 Dens of axis 21 Intervertebral disc Dissection of the brain with pia mater and arachnoid in situ.
Ether is evaporated from the ether layer using a rotary evaporator to obtain puriﬁed aniline order genuine shuddha guggulu online. In addition to the usual electrophilic substitutions purchase 60caps shuddha guggulu overnight delivery, naphthalene can also undergo oxidation and reduction reactions under speciﬁc conditions as outlined below purchase shuddha guggulu 60caps mastercard. Oxidation Oxidation of naphthalene by oxygen in the presence of vanadium pentoxide (V2O5) destroys one ring and yields phthalic anhydride (an important industrial process). N, O or S (hetero-atoms), in their rings are called heterocyclic compounds or heterocycles, e. N Pyridine Tetrahydrofuran Thiophene N is the hetero-atom O is the hetero-atom S is the hetero-atom Among the heterocyclic compounds, there are aromatic, e. Serotonin, a neuro- transmitter found in our body, is responsible for various bodily functions. However, there are some general rules to be followed in a heterocycle, especially in the use of sufﬁxes to indicate the ring size, saturation or unsaturation as shown in the following table. For example, from the name, pyridine, where the sufﬁx is -ine, one can understand that this heterocyclic compound contains nitrogen, has a six- membered ring system and is unsaturated. Ring with nitrogen Ring without nitrogen Ring size Maximum unsaturation Saturation Maximum unsaturation Saturation 3 irine iridine irene irane 4 ete etidine ete etane 5 ole olidine ole olane 6 ine – ine ane 7 epine – epine epane 8 ocine – ocine ocane 9 onine – onine onane 10 ecine – ecine ecane Monocyclic heterocycles containing three to ten members, and one or more hetero-atoms, are named systematically by using a preﬁx or preﬁxes to indicate the nature of the hetero-atoms as presented in the following table. Element Preﬁx Element Preﬁx Element Preﬁx O oxa P phospha Ge germa S thia As arsa Sn stanna Se selena Sb stiba Pb plumba Te tellura Bi bisma B bora N aza Si sila Hg mercura Two or more identical hetero-atoms are indicated by use of the multiplying preﬁxes di-, tri-ortetra-. When more than one distinct hetero-atom is present, the appropriate preﬁxes are cited in the name in descending order of group number in the periodic table, e. If both lie within the same group of the periodic table, then the order is determined by increasing atomic number, e. In unsaturated heterocycles, if the double bonds can be arranged in more than one way, their positions are deﬁned by indicating the N or C atoms that are not multiply bonded, and consequently carry an ‘extra’ hydrogen atom, by 1H-, 2H- and so on, for example 1H-azepine and 2H-azepine. H 2-Methylpyridine 5-Methylindole 3-Phenylthiophene Heterocyclic aromatic compounds can also have two or more hetero-atoms. If one of the hetero-atoms is a nitrogen atom, and the compound has a ﬁve- membered system, their names all end in -azole, and the rest of the name indicates other hetero-atoms. For example, pyrazole and imidazole are two isomeric heterocycles that contain two nitrogen atoms in the ring, thiazole has a sulphur atom and a nitrogen atom in the ring, and oxazole contains an oxygen atom and a nitrogen atom. In imidazole and oxazole, two hetero- atoms are separated by a carbon atom, whereas in their isomers, pyrazole and isoxazole, the hetero-atoms are directly linked to each other. The six- membered aromatic heterocycles with two nitrogens can exist in three isomeric forms, the most important being pyrimidine. For example, pyrrolidine, tetrahydrofuran, isoxazolidine and piperidine are fully saturated derivatives of pyrrole, furan, isoxazole and pyridine, respec- tively. This makes it extremely difﬁcult to generalize the physical properties of these compounds, because they vary signiﬁcantly depending on the saturation–unsaturation status, aromatic–nonaromatic behaviour, ring sizes and type and number of hetero-atoms present. Saturated hetero- cycles, known as alicyclic heterocycles, containing ﬁve or more atoms have physical and chemical properties typical of acyclic compounds that contain the same hetero-atoms. On the other hand, aromatic heterocycles display very characteristic and often complex reactivity. However, aromatic heterocycles show general patterns of reactivity associated with certain ‘molecular fragments’ such that the reactivity of a given heterocycle can be anticipated. Physical and chemical properties of selected important hetero- cyclic compounds are discussed under each compound sub-heading. In pyrrole, there are four p electrons, two short of the 2 Huckel¨ criteria for aromaticity. The nitrogen atom is sp -hybridized, formally containing a lone pair of electrons in the p orbital at right angles to the ring. However, the system delocalizes and pushes the lone pair of electrons into the ring to complete the sextet required for aromaticity. The nonbonding electrons on the nitrogen atom become a part of the aromatic sextet. However, biologically more signiﬁcant natural pyrroles are rather less simple; they are tetrameric pyrrole derivatives, known as porphyrins, e. Furan, also known as furane and furfuran, is an oxygen-containing ﬁve- membered aromatic heterocyclic compound that is usually produced when wood, especially pine wood, is distilled. Although it has a lone pair of electrons, these electrons cannot delocalize easily, and so the system is generally considered to be almost nonaromatic or weakly aromatic. The lone pair electrons of the sulphur are in the 3s orbital, and are less able to interact with the p electrons of the double bonds. S Acetylenic thiophene Physical properties of pyrrole, furan and thiophene Pyrrole is a weakly basic compound. However, as the nonbonding electrons on the nitrogen atom are part of the aromatic sextet, and no longer available for protonation, it has an extremely low basicity (pKa ¼$15). Pyrrole accepts a proton on one of the carbon atoms adjacent to the nitrogen atom, whereas the proton on the nitrogen atom can be removed by hydroxide ion to yield its conjugate base. The pair of nonbonding electrons on N in pyrrole is much less available for protonation than the pair on ammonia. While furan is extremely volatile and highly ﬂammable with a boiling point close to room temperature (31. Preparation of pyrrole, furan and thiophene A general way of synthesizing heterocyclic compounds is by cyclization of a dicarbonyl or diketo compound using a nucleophilic reagent that intro- duces the desired hetero-atom. Paal–Knorr synthesis It is a useful and straightforward method for the synthesis of ﬁve-membered heterocyclic compounds, e. Ammonia, primary amines, hydroxylamines or hydra- zines are used as the nitrogen component for the synthesis of pyrrole. In this reaction, a-haloketones react with 1,3-dicarbonyl compounds in the pre- sence of pyridine to yield substituted furan. However, the reactivity of this reaction varies signiﬁcantly among these heterocycles. The ease of electrophilic substitution is usually fur- an > pyrrole > thiophene > benzene. Clearly, all three heterocycles are more reactive than benzene towards electrophilic substitution. This reaction proceeds by formation of the electrophilic Vilsmeier complex, followed by electrophilic substitution of the heterocycle.