|
|||||||
![]() |
![]() |
||||||
|
Introduction to the Dictionary of Drugs Online
Introduction to the DOD databaseThe Chapman & Hall/CRC Chemical Database is a structured database holding information on chemical substances. It includes descriptive and numerical data on chemical, physical and biological properties of compounds; systematic and common names of compounds; literature references; structure diagrams and their associated connection tables. The Dictionary of Drugs Online is a subset of this database and includes all compounds contained in the Dictionary of Drugs (Main Work and Updates). Compound selection and presentationGeneral In general the following compounds are included:
Derivatives and variants Derivatives of compounds containing common functional groups are normally given under the parent compound e.g. hydrochlorides, esters, oximes, ethers, N- or S-oxides. Exceptions occur when a derivative has an extensive literature of its own, or where the derivative requires special stereochemical description which is best suited to diagrammatic representation e.g. chiral sulfoxides. In these cases the derivative entry is cross-referenced to the parent compound. Molecular formulae are included in DOD for nearly all of these derivatives and they can therefore readily be traced using the Molecular Formula Index whether they are documented as derivatives or have their own entry. Molecular formulae are not in general given for salts or hydrates. Where a derivative appears to have been characterised only as a salt, the properties of this salt may be given under the heading for the derivative. In such cases the data is clearly labelled e.g. Mp 179° (as hydrochloride). Where a compound can exist in several stereoisomeric forms, these isomers are grouped together into a single entry. Where known, physical properties, CAS registry numbers and pharmacological activity are assigned for each isomer. Antibiotic complexes and biologicals Many structurally related antibiotics co-occur as metabolites of the same producing organism, and these are presented within a single entry e.g. Actaplanin. Usually these components will only differ from each other in side chains or sugar residues and can be presented with a single structure diagram, suitably annotated. Complex biological molecules such as hormones have been treated in a manner, with closely related species variants subsumed into a single entry. An example is Calcitonin. Anions and cations For ionic substances such as quaternary ammonium salts, the entry refers to the anion or cation, and the molecular formula and molecular weight given are those of the ion. The various salts (e.g. chloride, nitrate) are treated as derivatives, each with its own molecular formula. Isotopically labelled compounds In general the coverage of DOD does not extend to isotopic variants. In cases where isotopes are used either medicinally or diagnostically, an entry for the unlabelled compound has been compiled and contains an explanation of the uses, plus additional CAS numbers applying to the isotopically labelled compound. Chemical names and synonymsEntry names Most entries are headed by a generic name but for some simpler compounds the systematic name is preferred as the entry name, in which case the entry name may be found from the generic name by using the Name Index. All generic names have suffixes to indicate their source (eg BAN, USAN). In some cases a generic name may strictly apply to a specific stereoisomer - Such examples carry annotations in the entry text. Synonyms The Dictionary contains a wide range of synonyms which may be (a) those found in the chemical literature (b) Chemical Abstracts names (these are omitted when excessively long) (c) company codes (d) tradenames used by pharmaceutical companies. Care has been taken to include as many tradenames, company codes and alternative names as possible. Most of these have been authenticated from the primary literature but in cases where this has not been possible the principal authorities are Negwer's Organic-Chemical Drugs and their Synonyms [5] and Martindale's Extra Pharmacopoeia [6]. Where a common drug has a very large number of tradenames, a cross reference is given to Negwer which should be consulted for the full listing. Proprietary ownership of drug names is not indicated, and the Dictionary should not be considered as an authoritative source on the proprietary ownership or use of these names. Synonyms are presented in the following order:
Spelling conventions American spelling is generally used for chemical names:
with some exceptions:
UK spelling is used throughout the text. Description of data typesFig. 1 illustrates the format of a typical entry within which individual types of data have been labelled. CAS Registry Numbers CAS Registry Numbers are identifying numbers allocated to each distinctly definable chemical substance indexed by the Chemical Abstracts Service since 1965 (plus retrospective allocation of numbers by CAS to compounds from the sixth and seventh collective index periods). The numbers have no chemical significance but they provide a label for each substance independent of any system of nomenclature.
In DOD, much effort has been expended to ensure that accurate CAS numbers are given for as many substances as possible. If a CAS number is not given for a particular compound, it may be (a) because CAS have not allocated one, or (b) very occasionally because an editorial decision cannot be made as to the correct number to cite. Additional registry numbers At the foot of the DOD entry, immediately before the references, may be shown additional registry numbers. These are numbers which have been recognised by the editors as belonging to the entry concerned but which cannot be unequivocally assigned to any of the compounds covered by the entry. Their main use will be in helping those who need to carry out additional searches, especially online searches in the CAS or other databases and who will be able to obtain additional hits using these numbers. Clearly, discretion is needed in their use for this purpose. Additional registry numbers may arise for a variety of reasons:
Structural formulae Every attempt has been made to present the structures of Chemical substance as accurately as possible according to best current practice and IUPAC recommendations. Structurally related compounds are presented Consistently and ring systems are oriented in a standard manner to allow ready comparison of structures. The pseudoatom abbreviations Me, Et and Ac for methyl, ethyl and acetyl respectively are used only when attached to a heteroatom. Ph is used throughout whether attached to carbon or a heteroatom. Other pseudoatom abbreviations such as Pri for isopropyl and Bz for benzoyl are not used. Peptides are usually drawn using the standard three letter abbreviations. The configurations of constituent amino acids are assumed to be L- unless otherwise stated. Stereochemical conventions [24] The absolute configuration of a compound is indicated where known . Where only one stereoisomer is referred to in the text of the entry, the structure diagram refers to that stereoisomer. Wherever possible, stereo structures are described using the Cahn-Ingold-Prelog sequence rule (R,S) and (E,Z) conventions [7], but in cases where these are cumbersome or inapplicable, alternatives such as the α,ß-system are used instead. Structure diagrams for compounds containing one or two chiral centres are given in DOD as Fischer-type diagrams showing the stereochemistry unequivocally. True Fischer diagrams in which the configuration is implied by the North-South-East-West positions of the substituents are widespread in the literature: although unambiguous they need to be used with caution by the inexperienced as they cannot be reoriented without the risk of introducing errors.
In a simple case, the four substituents about a Tetrahedral carbon atom are assigned priorities according to the CIP rules, and the molecule is then viewed from the side remote from the substituent of lowest priority. The configuration is (R) if the order of the three other groups from highest to lowest is clockwise, and (S) if it is anticlockwise. Extensions of the (R,S)-system refer to situations such as axial and planar chirality (e.g. biaryls, cyclophanes) and to molecules with central atoms other than carbon (e.g. sulfoxides). Where only the relative configuration of a compound containing more than one chiral centre is known, the symbols (R*) and (S*) are used, the lowest-numbered chiral centre being arbitrarily assigned the symbol (R*). For racemic modifications of compounds containing more than one chiral centre the symbols (RS) and (SR) are used, with the lowest-numbered chiral centre being arbitrarily assigned the symbol (RS). The racemate of a compound with a single chiral centre is described in DOD as (±)-. Molecular formula and molecular weight The elements in the molecular formulae are given according to the Hill convention (C,H, then other elements in alphabetical order). Molecular weights given are formula weights and are rounded to 3 places of decimals. In the case of high molecular mass substances, such as proteins, the value quoted may be that taken from an original literature source and may be an aggregate molar mass. Molecular formulae are not generally quoted for derivatives such as salts or hydrates. Pharmacological activity and therapeutic use Practically every compound in this Dictionary has been classified according to its mechanism of action (where this is known) and its therapeutic use and are assigned a Type of Compound code. Compounds which have several claimed therapeutic uses are indexed separately in each category. A full list of Type of Compound codes are given in the Help file. The assignment of drugs into each category is based on information given in Martindale [6], the most recent lists of approved names [l-4] or in the primary literature. This Dictionary is intended for medicinal and pharmaceutical chemists as an aid to research and is not intended as a guide to prescription or use of drugs. The information is given in good faith but the Editors cannot be held responsible for any inaccuracies therein. Nomenclature recommended in the annual supplements to Trends in Pharmacological Sciences [8] is used to summarise drug-receptor properties. Key papers on the biochemical mechanisms of drug actions are identified, and the main therapeutic effects of drugs are described together with any recent observations of new activities for existing drugs. For many drugs with chiral centres pharmacological activity can reside predominantly with one enantiomer. Any differences in potency between the different Stereoisomers of a particular compound are noted in DOD. The optimisation of drug activity is a continuing challenge for the medicinal chemist. Crystallographic and conformational studies as well as conventional structure-activity relationships (sar) are used in drug research to achieve this goal, and for many recently marketed products references to these areas of research are mentioned in DOD. Two indicators of drug absorption and distribution, pKa values and log P partition coefficients (octanol/water), are quoted for many entries. Development status This field gives information (when available) about whether a compound has been marketed, or is undergoing clinical trials. If a compound has been withdrawn from the market, this is also stated. Although a variety of sources have been consulted [2, 9], the transient nature of this type of information means that this dictionary should not be considered as an authoritative or up to date source for a drug's marketing status. Details of the worldwide top 100 prescription drugs (in 1994) are also provided [9]. Physical data Appearance
Organic compounds are assumed to be colourless unless
otherwise stated. An indication of crystal form and of
recrystallisation solvent is often given but these are
imprecise items of data- most organic compounds can be
crystallised from several solvent systems and the crystal
form often varies. Melting points and boiling points These are reported in degrees Celsius. The policy followed in cases of conflicting data is as follows:
Optical rotations These are given wherever possible and are expressed in the form: [α]D 20 + 30.6 (c, 1.2 in MeOH). This denotes a temperature of 20°C , wavelength at the sodium D line (589 nm) and a concentration of 1.2 9/100 ml in methanol solution. Where reported in the literature, an indication of optical purity (op) or enantiomeric excess (ee) is recorded after the rotation value. The degree sign following optical rotations, although still extensively found in the primary literature, has been dropped from DOD as it is dimensionally incorrect. Densities and refractive indices Although these are now of less importance for the identification of liquids than has been the case in the past, they are still quoted for common substances. Densities and refractive indices are not quoted where the determination appears to refer to an undefined mixture of stereoisomers. Solubilities Solubilities are quoted only where the solubility is unusual for an organic compound. Typical organic compounds are soluble in the usual organic solvents such as ether and chloroform, and virtually insoluble in water. pKa values Experimentally determined pKa values are given for both acids and bases. The pKa of a base can be obtained by subtracting its pKa from 14.17(at 20° C) or from 14.00 (at 25° C). An indication of the ionisation of a compound at a particular pH is invaluable for predicting its potential pharmacological profile, hence pKa values are reported for as many compounds as possible. Octanol-water partition cofficients Octanol-water partition coefficients are a useful measure of a compound's lipophilicity, and hence its potential biodistribution [10]. In an attempt to provide comprehensive coverage of this important area, both experimental and calculated values have been included for as many compounds as possible. Experimental partition coefficients are denoted by the suffix 'exp' in parentheses. The majority of values have been supplied by the LOGKOW database* and these are indicated by the symbol s. Experimental values without the s symbol are as reported in the primary literature. Calculated partition coefficients are denoted by the suffix 'calc' in parentheses. These have been calculated by Tripos, Inc.† using the Hansch and Leo algorithm CLOGP [11]. In special circumstances the degree of error is unusually large - such values carry the epithet 'uncertain' to highlight this.
Hazard and Toxicity InformationGeneral
Toxicity and hazard information is highlighted by the
sign An important function of DOD is to alert the user to Potential hazards associated with the use of a compound. All hazard and toxicity data in DOD has been carefully and critically assessed by a specialist editor. Brief summaries of hazard and toxicity information have been included for many pharmacological agents, although the absence of such data cannot be taken as an indication of safety in use and the publishers cannot be held responsible for any inaccuracies in the reported information. Physical, reactive and toxic properties all contribute to the hazard associated with a particular chemical. As part of the physical data, flash points, explosive limits and autoignition temperatures have been included where appropriate. Flammability classifications, which are based on flash point measurements and boiling points, are also mentioned, and the opportunity has been taken to include UK occupational exposure standards, or for some compounds threshold limit values published by the American Conference of Governmental Industrial Hygienists (ACGIH). For the reactive hazards, a brief comment is made on any explosive (or violent polymerisation) properties and aspects of the chemical reactivity of a substance which are of concern. These include the potential for peroxidation, oxidising/reducing properties and incompatibility with commonly available chemicals. Toxicity information has been chosen to show hazardous effects from short-term or long-term exposure. Observations from human exposure are summarised if available (including adverse effects when handling drugs), otherwise experimental tests are quoted. Included in the toxicity data are results of irritancy tests, acute lethality data, target organ toxicity, and carcinogenic and reproductive properties where appropriate. Those chemicals which have been classified by the International Agency for Research on Cancer (IARC) as human carcinogens, probable carcinogens or possible human carcinogens have been identified in the Dictionary accordingly. Although drug toxicity usually implies any adverse effects following the administration of a drug, the hazards of handling many classes of drugs in the workplace should not be overlooked [12-18]. Strict hygiene and compliance with local safety rules are necessary when handling prostaglandins, antineoplastic alkylating agents, immunosuppressants, synthetic estrogens and adrenocorticosteroids and known allergens, in addition to the usual precautions for working with pharmacological agents whatever their hazard profile. The selection of drug-induced toxicity data for DOD is drawn mainly from available animal studies and reviews of adverse effects in humans. Acute lethality data (usually expressed as LD50 or sometimes LDLo - the lowest dose reported to have caused death) are quoted for one animal species (usually a rodent) by an oral and one parenteral route of administration. Information on the chronic toxicity of drugs following long-term or repeated exposure in animals is relatively scarce in the literature. Pertinent references are included, however, as is a mention of any effects on the male and female reproductive systems and the developmental toxicity of drugs. For many drugs a fuller explanation of the observations of reproductive and teratogenic tests quoted in DOD is available [19]. Genotoxicity rests and long-term safety evaluation studies used by the pharmaceutical industry for drug development and licence applications are currently being scrutinised [20,21]. Brief comments in DOD on the adverse human effects of drugs are intended to reinforce the general precautions necessary when handling pharmacological agents. More comprehensive reviews of adverse drug reactions, particularly for the major classes of drugs in use today, have been published [6, 22]. No attempt has been made in DOD to summarise the enhancement(or otherwise) of drug potency and toxicity by interaction with other drugs or with dietary components [23]. RTECS® Accession Numbers** Many entries in DOD contain one or more RTECS® Accession Numbers. Possession of these numbers allows users to locate toxicity information on relevant substances from the MOSH Registry of Toxic Effects of Chemical Substances, which is a compendium of toxicity data extracted from the scientific literature. For each Accession Number the RTECS® database provides the following data when available: substance prime name and synonyms; date when the substance record was last updated; CAS Registry Numbers; molecular formula and weight; reproductive, tumorigenic, and toxic dose data; citations to aquatic toxicity ratings, IARC reviews, ACGIH Threshold Limit Values, toxicological reviews, existing Federal standards, the NIOSH criteria document program for recommended standards, the NIOSH current intelligence program, the NCI Carcinogenesis Testing Program, and the EPA Toxic Substances Control Act inventory. The NIOSH Registry of Toxic Effects of Chemical Substances is available in the following forms:
Bibliographic references and literature coverageEach entry is accompanied by a selection of literature references, the aim of which is to facilitate entry into the literature for the user who wishes to locate more detailed information about a particular compound. Thus in general, recent references are preferred to older ones, particularly for chiral compounds where optical purity and absolute configuration may have been determined only relatively recently. Extensive use is made of review articles, especially for very widely used compounds which have been known for a long time. Therefore, the number of references quoted cannot be taken as a measure of relative importance of a compound. References are given in date order except for references to spectroscopic library collections, which sort at the top of the list, and those to hazard/toxicity sources which sort at the bottom. For many compounds, especially those still undergoing clinical trials, the only information available may be in the patent literature. Wherever possible the original patents (or English language equivalents) have been consulted, and details of biological activity and physical properties are as quoted in these documents. When referring to a patent no distinction is made between patent applications and granted patents. As well as quoting the patent office and patent number, a CAS reference and the patenting company are also given. Patents are usually quoted in the following format: Eur Pat., 247 458 (1987) (Glaxo); CA, 116, 7887q (synth) Extensive reference has been made to post- 1990 pharmacological and biochemical literature. These changes reflect current interests in, for example, drug receptor interactions, anti-HIV agents, drugs which modulate the immune system, and the therapeutic uses of natural products and their derivatives. In addition to citations of pharmacological mechanisms, references to pharmacokinetic and metabolic studies and to clinical trials are included for many entries together with the more recent hplc/capillary gc methods for analysing drugs in biological matrices. The contents of most references are indicated by means of suffixes eg (synth), (pharmacokinet). Some suffixes are now given in boldface type, where the editors consider the reference to be especially important. In general journal abbreviations are uniform with the Chemical Abstracts Service Source Index (CASSI) except for a short list of very common journals where we have been able to save space by using well understood short-form abbreviations. The full list of these is as follows:
Entry under reviewThe database is continually under updated. When an entry is undergoing revision at the time of an on-line release (e.g. by addition of further derivatives or references), this is indicated by a message at the head of the entry. Abbreviations
References
*The LOGKOW database is compiled and updated by Dr James Sangster of Sangster Research Laboratories of Montreal, Quebec, Canada and is included in the Dictionary of Pharmacological Agents with the permission of Technical Database Services, Inc. The LOGKOW database is available on diskettes and as an online service from TDS Numerica. For information please contact TDS, 135 West 50th Street, New York, NY 10020. Phone: 212 245 0044. Fax: 212 247 0587.E -mail:numerica@tds_tds.com NumericaTM materials and services are secured from reliable sources. However, neither TDS nor the author of the LOGKOW database, makes any warranty or shall have any responsibility or liability of any kind in respect of any information provided or any results of application of such information in research or otherwise. In no event shall TDS or NumericaTM authors or suppliers be liable for any damages, lost profits, or consequential exemplary or special damages, even if TDS or its authors suppliers have been advised of the possibility of such damages. Copyright and all other proprietary rights in and to all portions of NumericaTM are strictly reserved by TDS and the NumericaTM authors. NumericaTM is provided for the user's own internal use only. The user shall comply with copyright law. **RTECS® Accession Numbers are compiled and distributed by the National Institute for Occupational Safety and Health Service of the U.S. Department of Health and Human Services of the United States of America. All rights reserved (1996).
†TRIPOS, Inc., 1699 S. Hanley Road, St Louis, MO, USA. Phone:
314 647 1099, 800 323 2960. Fax: 314 647 9241
|
|
DOD 14.1 Copyright © 2010 Taylor & Francis Group All Rights Reserved |