Simplified molecular-input line-entry system
The simplified molecular-input line-entry system is a specification in the form of a line notation for describing the structure of chemical species using short ASCII strings. SMILES strings can be imported by most molecule editors for conversion back into two-dimensional drawings or three-dimensional models of the molecules; the original SMILES specification was initiated in the 1980s. It has since been extended. In 2007, an open standard called. Other linear notations include the Wiswesser line notation, ROSDAL, SYBYL Line Notation; the original SMILES specification was initiated by David Weininger at the USEPA Mid-Continent Ecology Division Laboratory in Duluth in the 1980s. Acknowledged for their parts in the early development were "Gilman Veith and Rose Russo and Albert Leo and Corwin Hansch for supporting the work, Arthur Weininger and Jeremy Scofield for assistance in programming the system." The Environmental Protection Agency funded the initial project to develop SMILES. It has since been modified and extended by others, most notably by Daylight Chemical Information Systems.
In 2007, an open standard called "OpenSMILES" was developed by the Blue Obelisk open-source chemistry community. Other'linear' notations include the Wiswesser Line Notation, ROSDAL and SLN. In July 2006, the IUPAC introduced the InChI as a standard for formula representation. SMILES is considered to have the advantage of being more human-readable than InChI; the term SMILES refers to a line notation for encoding molecular structures and specific instances should be called SMILES strings. However, the term SMILES is commonly used to refer to both a single SMILES string and a number of SMILES strings; the terms "canonical" and "isomeric" can lead to some confusion when applied to SMILES. The terms are not mutually exclusive. A number of valid SMILES strings can be written for a molecule. For example, CCO, OCC and CC all specify the structure of ethanol. Algorithms have been developed to generate the same SMILES string for a given molecule; this SMILES is unique for each structure, although dependent on the canonicalization algorithm used to generate it, is termed the canonical SMILES.
These algorithms first convert the SMILES to an internal representation of the molecular structure. Various algorithms for generating canonical SMILES have been developed and include those by Daylight Chemical Information Systems, OpenEye Scientific Software, MEDIT, Chemical Computing Group, MolSoft LLC, the Chemistry Development Kit. A common application of canonical SMILES is indexing and ensuring uniqueness of molecules in a database; the original paper that described the CANGEN algorithm claimed to generate unique SMILES strings for graphs representing molecules, but the algorithm fails for a number of simple cases and cannot be considered a correct method for representing a graph canonically. There is no systematic comparison across commercial software to test if such flaws exist in those packages. SMILES notation allows the specification of configuration at tetrahedral centers, double bond geometry; these are structural features that cannot be specified by connectivity alone and SMILES which encode this information are termed isomeric SMILES.
A notable feature of these rules is. The term isomeric SMILES is applied to SMILES in which isotopes are specified. In terms of a graph-based computational procedure, SMILES is a string obtained by printing the symbol nodes encountered in a depth-first tree traversal of a chemical graph; the chemical graph is first trimmed to remove hydrogen atoms and cycles are broken to turn it into a spanning tree. Where cycles have been broken, numeric suffix labels are included to indicate the connected nodes. Parentheses are used to indicate points of branching on the tree; the resultant SMILES form depends on the choices: of the bonds chosen to break cycles, of the starting atom used for the depth-first traversal, of the order in which branches are listed when encountered. Atoms are represented by the standard abbreviation of the chemical elements, in square brackets, such as for gold. Brackets may be omitted in the common case of atoms which: are in the "organic subset" of B, C, N, O, P, S, F, Cl, Br, or I, have no formal charge, have the number of hydrogens attached implied by the SMILES valence model, are the normal isotopes, are not chiral centers.
All other elements must be enclosed in brackets, have charges and hydrogens shown explicitly. For instance, the SMILES for water may be written as either O or. Hydrogen may be written as a separate atom; when brackets are used, the symbol H is added if the atom in brackets is bonded to one or more hydrogen, followed by the number of hydrogen atoms if greater than 1 by the sign + for a positive charge or by - for a negative charge. For example, for ammonium. If there is more than one charge, it is written as digit.
European Chemicals Agency
The European Chemicals Agency is an agency of the European Union which manages the technical and administrative aspects of the implementation of the European Union regulation called Registration, Evaluation and Restriction of Chemicals. ECHA is the driving force among regulatory authorities in implementing the EU's chemicals legislation. ECHA helps companies to comply with the legislation, advances the safe use of chemicals, provides information on chemicals and addresses chemicals of concern, it is located in Finland. The agency headed by Executive Director Bjorn Hansen, started working on 1 June 2007; the REACH Regulation requires companies to provide information on the hazards and safe use of chemical substances that they manufacture or import. Companies register this information with ECHA and it is freely available on their website. So far, thousands of the most hazardous and the most used substances have been registered; the information is technical but gives detail on the impact of each chemical on people and the environment.
This gives European consumers the right to ask retailers whether the goods they buy contain dangerous substances. The Classification and Packaging Regulation introduces a globally harmonised system for classifying and labelling chemicals into the EU; this worldwide system makes it easier for workers and consumers to know the effects of chemicals and how to use products safely because the labels on products are now the same throughout the world. Companies need to notify ECHA of the labelling of their chemicals. So far, ECHA has received over 5 million notifications for more than 100 000 substances; the information is available on their website. Consumers can check chemicals in the products. Biocidal products include, for example, insect disinfectants used in hospitals; the Biocidal Products Regulation ensures that there is enough information about these products so that consumers can use them safely. ECHA is responsible for implementing the regulation; the law on Prior Informed Consent sets guidelines for the import of hazardous chemicals.
Through this mechanism, countries due to receive hazardous chemicals are informed in advance and have the possibility of rejecting their import. Substances that may have serious effects on human health and the environment are identified as Substances of Very High Concern 1; these are substances which cause cancer, mutation or are toxic to reproduction as well as substances which persist in the body or the environment and do not break down. Other substances considered. Companies manufacturing or importing articles containing these substances in a concentration above 0,1% weight of the article, have legal obligations, they are required to inform users about the presence of the substance and therefore how to use it safely. Consumers have the right to ask the retailer whether these substances are present in the products they buy. Once a substance has been identified in the EU as being of high concern, it will be added to a list; this list is available on ECHA's website and shows consumers and industry which chemicals are identified as SVHCs.
Substances placed on the Candidate List can move to another list. This means that, after a given date, companies will not be allowed to place the substance on the market or to use it, unless they have been given prior authorisation to do so by ECHA. One of the main aims of this listing process is to phase out SVHCs where possible. In its 2018 substance evaluation progress report, ECHA said chemical companies failed to provide “important safety information” in nearly three quarters of cases checked that year. "The numbers show a similar picture to previous years" the report said. The agency noted that member states need to develop risk management measures to control unsafe commercial use of chemicals in 71% of the substances checked. Executive Director Bjorn Hansen called non-compliance with REACH a "worry". Industry group CEFIC acknowledged the problem; the European Environmental Bureau called for faster enforcement to minimise chemical exposure. European Chemicals Bureau Official website
Artemisia is a large, diverse genus of plants with between 200 and 400 species belonging to the daisy family Asteraceae. Common names for various species in the genus include mugwort and sagebrush. Artemisia comprises hardy herbaceous plants and shrubs, which are known for the powerful chemical constituents in their essential oils. Artemisia species grow in temperate climates of both hemispheres in dry or semiarid habitats. Notable species include A. vulgaris, A. tridentata, A. annua, A. absinthium, A. dracunculus, A. abrotanum. The leaves of many species are covered with white hairs. Most species have strong aromas and bitter tastes from terpenoids and sesquiterpene lactones, which discourage herbivory, may have had a selective advantage; the small flowers are wind-pollinated. Artemisia species are used as food plants by the larvae of a number of Lepidoptera species; some botanists split the genus into several genera, but DNA analysis does not support the maintenance of the genera Crossostephium, Neopallasia and Sphaeromeria.
Some of the species are called sages, causing confusion with the Salvia sages in the family Lamiaceae. The name "artemisia" derives from the Greek goddess Artemis, the namesake of Greek Queens Artemisia I and II. A more specific reference may be to Artemisia II of Caria, a botanist and medical researcher who died in 350 BC; the aromatic leaves of some species are used for flavouring. Most species have an bitter taste. A. dracunculus is used as a culinary herb important in French cuisine. Artemisia vulgaris was used to repel midges and moths, intestinal worms, in brewing as a remedy against hangovers and nightmares. Artemisia absinthium is used to make the potent spirits absinthe. Malört contains wormwood; the aperitif vermouth is a wine flavored with aromatic herbs, but with wormwood. Artemisia arborescens is an aromatic herb indigenous to the Middle East used in tea with mint. A few species are grown as the fine-textured ones used for clipped bordering. All grow best in free-draining sandy soil, in full sun.
Artemisia stelleriana is known as Dusty Miller, but several other species bear that name, including Jacobaea maritima, Silene coronaria, Centaurea cineraria. The largest collection of living Artemisia species and cultivars is held in the National Collection of Artemisia in Sidmouth, Devon, UK, which holds about 400 taxa; the National Collection scheme is administered by Plant Heritage in the British Isles. Artemisinin and derivatives are a group of compounds with the most rapid action of all current drugs used to treat malaria. Treatments containing an artemisinin derivative are now standard treatment worldwide for malaria caused by Plasmodium falciparum. Artemisia cina and other Old World species are the source of santonin. Chinese mugwort, Artemisia argyi, is used in traditional Chinese medicine. Artemisia capillaris Thunberg has been found to have potent sedative-hypnotic effects, which are mediated through potentiation of the GABAA receptor- Cl− ion channel complex Artemisia austriaca has beneficial effects in reducing the withdrawal syndrome of morphine.
Artemisia has been used in popular culture for centuries. A few examples are: Artemisia herba-alba is thought to be the plant translated as "wormwood" in English language versions of the Bible. Wormwood is mentioned seven times in the Jewish Bible, always with the implication of bitterness, it is mentioned once in the New Testament. Wormwood is the "name of the star" in the Book of Revelation 8:11 that John of Patmos envisions as cast by the angel and falling into the waters, making them undrinkably bitter. Further references in the Bible show wormwood was a common herb known for its bitter taste. In Shakespeare's Hamlet, the titular character says "Wormwood, wormwood" to comment on the bitter implications of what the Player Queen has just said. Classification of Artemisia is difficult. Divisions of Artemisia prior to 2000 into subgenera or sections have not been backed up by molecular data, but much of the molecular data, as of 2006, are not strong; the following identified. Section Tridentatae consists of eleven to thirteen species of coarse shrubs, which are prominent parts of the flora in western North America.
In some classifications, they are part of the genus or subgenus Seriphidium, although recent studies have contested this lineage to Old World species. Tridentatae was first articulated as a section by Rydberg in 1916, it was not until McArthur et al. in 1981 that Tridentatae was elevated to a separate subgenus from Seriphidium. The principal motive for their separation was geographical distribution, chemical makeup, karyotype. Much of the debate surrounding Tridentatae is phytogeographic, thus habitat and geography are cited when understanding the evolution of this endemic North American subgenus. Evolutionary cycles of wet and dry climates encouraged “dip
Salvia is the largest genus of plants in the mint family, with nearly 1000 species of shrubs, herbaceous perennials, annuals. Within the Lamiaceae, Salvia is part of the tribe Mentheae within the subfamily Nepetoideae. One of several genera referred to as sage, it includes the produced herb used in cooking, Salvia officinalis; the genus is distributed throughout the Old World and the Americas, with three distinct regions of diversity: Central and South America. The name Salvia derives from the Latin salvere, the verb related to salus, referring to the herb's healing properties. Pliny the Elder was the first author known to describe a plant called "Salvia" by the Romans describing the type species for the genus Salvia, Salvia officinalis; the common modern English name sage derives from Middle English sawge, borrowed from Old French sauge, like the botanical name, stems from Latin salvere. When used without modifiers, the name'sage' refers to Salvia officinalis; the ornamental species are referred to by their genus name Salvia.
Salvia species include biennial, or perennial herbs, along with woody subshrubs. The stems are angled like other members in Lamiaceae; the leaves are entire, but sometimes toothed or pinnately divided. The flowering stems bear small bracts, dissimilar to the basal leaves—in some species the bracts are ornamental and showy; the flowers are produced in racemes, or panicles, produce a showy display with flower colors ranging from blue to red, with white and yellow less common. The calyx is tubular or bell shaped, without bearded throats, divided into two parts or lips, the upper lip entire or three-toothed, the lower two-cleft; the corollas are claw shaped and are two-lipped. The upper lip is entire or three-toothed; the lower lip has two lobes. The stamens are reduced to two short structures with anthers two-celled, the upper cell fertile, the lower imperfect; the flower styles are two-cleft. The fruits are smooth ovoid or oblong nutlets and in many species they have a mucilaginous coating. Many members of Salvia have trichomes growing on the leaves and flowers, which help to reduce water loss in some species.
Sometimes the hairs are glandular and secrete volatile oils that give a distinct aroma to the plant. When the hairs are rubbed or brushed, some of the oil-bearing cells are ruptured; this results in the plant being unattractive to grazing animals and some insects. The defining characteristic of the genus Salvia is the unusual pollination mechanism, it is central to any investigation into the systematics, species radiation, or pollination biology of Salvia. It consists of two stamens and the two thecae on each stamen are separated by an elongate connective, it is the elongation of the connective. Sprengel was the first to describe the nototribic pollination mechanism in Salvia; when a pollinator probes a male stage flower for nectar, the lever causes the stamens to move and the pollen to be deposited on the pollinator. When the pollinator withdraws from the flower, the lever returns the stamens to their original position. In older, female stage flowers, the stigma is bent down in a general location that corresponds to where the pollen was deposited on the pollinator's body.
The lever of most Salvia species is not specialized for a single pollinator, but is generic and selected to be released by many bird and bee pollinators of varying shapes and sizes. The lever arm can be specialized to be different lengths so that the pollen is deposited on different parts of the pollinator’s body. For example, if a bee went to one flower and pollen was deposited on the far back of her body, but it flew to another flower where the stigma was more forward, pollination could not take place; this can result in reproductive isolation from the parental population and new speciation can occur. It is believed that the lever mechanism is a key factor in the speciation, adaptive radiation, diversity of this large genus. George Bentham was first to give a full monographic account of the genus in 1832–1836, based his classifications on staminal morphology. Bentham's work on classifying the family Labiatae is still the only comprehensive and global organization of the family. While he was clear about the integrity of the overall family, he was less confident about his organization of Salvia, the largest genus in Labiatae.
Based on his own philosophy of classification, he wrote that he "ought to have formed five or six genera" out of Salvia. In the end, he felt that the advantage in placing a uniform grouping in one genus was "more than counterbalanced by the necessity of changing more than two hundred names." At that time there were only 291 known Salvia species. Bentham organized Salvia into twelve sections, based on differences in corolla and stamens; these were placed into four subgenera that were divided into Old World and New World species: Subgenus Salvia: Old World Subgenus Sclarea: Old World Subgenus Calosphace: N
Arrabidaea chica is a medicinal plant in the Bignoniaceae family used for cosmetics. The leaves are source of chica. Tropical Plant Database: Arrabidaea chica
The Jmol applet, among other abilities, offers an alternative to the Chime plug-in, no longer under active development. While Jmol has many features that Chime lacks, it does not claim to reproduce all Chime functions, most notably, the Sculpt mode. Chime requires plug-in installation and Internet Explorer 6.0 or Firefox 2.0 on Microsoft Windows, or Netscape Communicator 4.8 on Mac OS 9. Jmol operates on a wide variety of platforms. For example, Jmol is functional in Mozilla Firefox, Internet Explorer, Google Chrome, Safari. Chemistry Development Kit Comparison of software for molecular mechanics modeling Jmol extension for MediaWiki List of molecular graphics systems Molecular graphics Molecule editor Proteopedia PyMOL SAMSON Official website Wiki with listings of websites and moodles Willighagen, Egon. "Fast and Scriptable Molecular Graphics in Web Browsers without Java3D". Doi:10.1038/npre.2007.50.1