コデイン 化学特性,用途語,生産方法
解説
モルヒネ型アヘンアルカロイドの一種．アヘン中に0.7～2.5％ 含まれるが，おもにモルヒネのメチル化により合成されるコデイン．
性質
通常，一水和物として無色の斜方晶となる．融点154～156 ℃．[α]D15"－136°(エタノール)．水に微溶，エタノールに可溶.
用途
呼吸中枢に作用するので，リン酸塩を咳止め薬，鎮痛薬として用いる．
毒性
LD50 290 mg/kg(マウス，経口)．
説明
Codein phosphate and hydrochloride caused contact
dermatitis in a worker in the production of opium
alkaloids. Codeine bitartrate caused contact dermatitis
in a worker in the production of concentrated poppy
straw. Codeine was a sensitizer in a laboratory worker
at an opiate-manufacturing pharmaceutical company,
also sensitive to the baine.
化学的特性
Codeine, also known as methylmorphine, C18H21NO3· H2O, is a colorless white crystalline substance, slightly soluble in water, soluble in alcohol and chloroform, effloresces slowly in dry air.
使用
Codeine is used in medicine for its narcoticanalgesic action. It is used as a sedative incough mixtures. Codeine occurs in opiumfrom 0.7% to 2.5%. It is prepared frommorphine by methylating the phenolic OHgroup of the morphine. It is also obtained byextraction of opium.
定義
codeine: An alkaloid C
18H
21NO
3found in opium. It is structurally similarto morphine, from which it isproduced, and is used in the form ofthe sulphate or phosphate as apainkiller and cough medicine.Codeine is converted into morphinein the liver. It is used to some extentas a recreational drug. In the UK it isa class B drug but can be obtained incomposite over-the-counter preparationsin which it has a low concentrationand is combined with paracetamolor ibuprofen. See also opioids.
世界保健機関（WHO）
Codeine, which has antitussive, opioid analgesic and antidianhoeal
activity, was first extracted from opium in 1832 and has since been widely used in
medicine. The development of dependence and its potential for abuse resulted in
the control af the substance under Schedule II of the 1961 Single Convention on
Narcotic Drugs. Preparations containing codeine remain widely available and are
included in the WHO Model List of Essential Drugs.(Reference: (WHTAC1) The Use of Essential Drugs, 2nd Report of the WHO Expert
Committee, 722, , 1985)
生物学の機能
Like morphine, codeine is a naturally occurring opioid
found in the poppy plant. Codeine is indicated for the
treatment of mild to moderate pain and for its antitussive
effects. It is widely used as an opioid antitussive because
at antitussive doses it has few side effects and has
excellent oral bioavailability. Codeine is metabolized in
part to morphine, which is believed to account for its
analgesic effect. It is one of the most commonly used
opioids in combination with nonopioids for the relief of
pain. The administration of 30 mg of codeine in combination
with aspirin is equivalent in analgesic effect to
the administration of 65 mg of codeine. The combination
of the drugs has the advantage of reducing the amount of opioid required for pain relief and abolition
of the pain via two distinct mechanisms, inhibition of
prostanoid synthesis and opioid inhibition of nociceptive
transmission. When given alone, orally administered
codeine has about one-tenth to one-fifth the potency
of morphine for the relief of pain. In addition, IV
codeine has a greater tendency to release histamine and
produce vasodilation and hypotension than does morphine.
Thus, the use of IV codeine is rare. Codeine is
rarely addictive and produces little euphoria.
一般的な説明
Codeine is an alkaloid that occurs naturally in opium, butthe amount present is usually too small to be of commercialimportance. Consequently, most commercial codeine is preparedfrom morphine by methylating the phenolic OHgroup. It occurs as levorotatory, colorless, efflorescent crystals,or as a white crystalline powder. It is light sensitive.Codeine is a monoacidic base and readily forms salts withacids, with the most important being the sulfate and thephosphate. The acetate and methylbromide derivatives havebeen used to a limited extent in cough preparations.The general pharmacological action of codeine is similarto that of morphine, but it does not possess the sameanalgesic potency.
空気と水の反応
CODEINE is light sensitive and sensitive to prolonged exposure to air. Insoluble in water.
反応プロフィール
CODEINE is incompatible with bromides, iodides and salts of heavy metals. . CODEINE is an amine. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.
危険性
Habit-forming narcotic, sale legally
restricted.
健康ハザード
The toxic effects due to codeine are similarbut less toxic than those of morphineand other opium alkaloids. An overdosecan cause respiratory failure. It is a weakdepressant of the central nervous system.It also exhibits stimulant action. Toxicsymptoms from high dosages may includedrowsiness, sleep, tremors, excitement, andhallucinations. It may also produce gastricpains and constipation. An oral LD50 value in rats is 427 mg/kg. The habit-forming effectsof codeine are lower than those associatedwith morphine.
Nagamatsu and coworkers (1985) havereported in vitro formation of codeinonefrom codeine by rat or guinea pig liverhomogenate. Codeinone may be a metabolicintermediate in the presence of nicotinamideadenine dinucleotide (NAD). Its acute toxicityin mice was determined to be 30 timeshigher than that of codeine.
火災危険
CODEINE is combustible.
接触アレルゲン
Codeine has been reported as an occupational sensitizer
in workers in the production of opium alkaloids.
Codeine has been responsible for fixed drug eruptions
or generalized dermatitis. Cross-sensitivity is expected
to morphine.
薬理学
Codeine is a constituent of opium. Up to 10% of a dose of codeine is
metabolised by the hepatic microsomal enzyme CYP2D6 to morphine, which
contributes significantly to its analgesic effect. The rest is metabolised in the
liver to norcodeine and then conjugated to produce glucuronide conjugates
of codeine, norcodeine and morphine. Codeine is considerably less potent
than morphine. A round 8% of Western Europeans are deficient in the
CYP2D6 enzyme and may not experience adequate analgesia with codeine.
S imilarly, with super-metabolisers, there may be problems with opioid
toxicity; particular care is needed in the breastfeeding mother as morphine is
transferred in milk. Codeine can cause significant histamine release, and
intravenous administration should be avoided. It has marked antitussive
effects and also causes significant constipation. It is often combined with
paracetamol.
純化方法
Codeine crystallises from water or aqueous EtOH. Dry it at 80o. Evaporation of a CHCl3 extract gives a colourless glass which crystallises on scratching. It crystallises from H2O as the monohydrate, m 157-158.5o, and has [] D -136o (c 2.8, EtOH). The hydrobromide crystallises in needles from H2O, and effervesces at 151-160o, solidifies and remelts with extensive decomposition at 273-278o. It sublimes at 100o/0.03mm. [Gates J Am Chem Soc 75 4340 1953, Dauben et al. J Org Chem 44 1567 1979, Beilstein 27 II 136, 27 III/IV 2228.]
コデイン 上流と下流の製品情報
原材料
準備製品