Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereoisomers, which by definition have the same molecular formula and sequence of bonded atoms (constitution), but differ in the geometric positioning of the atoms in space. For this reason, it is also known as 3D chemistry—the prefix "stereo-" means "three-dimensionality".
In chemistry, a racemic mixture or racemate, is one that has equal amounts of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates.
The Bristol-Myers Squibb Company, doing business as Bristol Myers Squibb (BMS), is an American multinational pharmaceutical company. Headquartered in Princeton, New Jersey, BMS is one of the world's largest pharmaceutical companies and consistently ranks on the Fortune 500 list of the largest U.S. corporations. For fiscal 2022, it had a total revenue of $46.2 billion.
In chemistry, racemization is a conversion, by heat or by chemical reaction, of an optically active compound into a racemic form. This creates a 1:1 molar ratio of enantiomers and is referred to as a racemic mixture. Plus and minus forms are called Dextrorotation and levorotation. The D and L enantiomers are present in equal quantities, the resulting sample is described as a racemic mixture or a racemate. Racemization can proceed through a number of different mechanisms, and it has particular significance in pharmacology as different enantiomers may have different pharmaceutical effects.
In stereochemistry, an epimer is one of a pair of diastereomers. The two epimers have opposite configuration at only one stereogenic center out of at least two. All other stereogenic centers in the molecules are the same in each. Epimerization is the interconversion of one epimer to the other epimer.
Vincristine, also known as leurocristine and marketed under the brand name Oncovin among others, is a chemotherapy medication used to treat a number of types of cancer. This includes acute lymphocytic leukemia, acute myeloid leukemia, Hodgkin's disease, neuroblastoma, and small cell lung cancer among others. It is given intravenously.
In chemistry, stereoselectivity is the property of a chemical reaction in which a single reactant forms an unequal mixture of stereoisomers during a non-stereospecific creation of a new stereocenter or during a non-stereospecific transformation of a pre-existing one. The selectivity arises from differences in steric and electronic effects in the mechanistic pathways leading to the different products. Stereoselectivity can vary in degree but it can never be total since the activation energy difference between the two pathways is finite: both products are at least possible and merely differ in amount. However, in favorable cases, the minor stereoisomer may not be detectable by the analytic methods used.
The pharmaceutical industry in India was valued at an estimated US$42 billion in 2021 and is estimated to reach $130 billion by 2030. India is the world's largest provider of generic medicines by volume, with a 20% share of total global pharmaceutical exports. It is also the largest vaccine supplier in the world by volume, accounting for more than 60% of all vaccines manufactured in the world. Indian pharmaceutical products are exported to various regulated markets including the US, UK, European Union and Canada.
Otsuka Pharmaceutical Co., Ltd., abbreviated OPC, is a pharmaceutical company headquartered in Tokyo, Osaka and Naruto, Japan. The company was established August 10, 1964.
Area codes 304 and 681 are telephone area codes in the North American Numbering Plan (NANP) for the entirety of the U.S. state of West Virginia. The numbering plan area was established in October 1947 with area code 304, as one of the eighty-six original North American area codes. Area code 681 was added to the same area in an overlay plan that took effect on March 28, 2009.
Allylamine is an organic compound with the formula C3H5NH2. This colorless liquid is the simplest stable unsaturated amine.
ISIS/Draw was a chemical structure drawing program developed by MDL Information Systems. It introduced a number of file formats for the storage of chemical information that have become industry standards.
Quinagolide (INNTooltip International nonproprietary name, BANTooltip British Approved Name), sold under the brand name Norprolac, is a selective dopamine D2 receptor agonist which is used to reduce elevated levels of prolactin (hyperprolactinemia). It has also been found to be effective in the treatment of breast pain. It is used in the UK, but it is not available in US.
Delphinine is a toxic diterpenoid alkaloid found in plants from the Delphinium (larkspur) and Atragene genera, both in the family Ranunculaceae. Delphinine is the principal alkaloid found in Delphinium staphisagria seeds – at one time, under the name stavesacre, a very well known herbal treatment for body lice. It is related in structure and has similar effects to aconitine, acting as an allosteric modulator of voltage gated sodium channels, and producing low blood pressure, slowed heart rate and abnormal heart rhythms. These effects make it highly poisonous. While it has been used in some alternative medicines, most of the medical community does not recommend using it due to its extreme toxicity.
The 60 Plus American Association of Senior Citizens is an American conservative advocacy group founded in 1992 and based in Alexandria, Virginia. Its stated purpose is to promote solutions to seniors' issues that are grounded in free markets, less government, and less taxes. The organization is pro-Republican Party. The organization is known for its advocacy for the privatization of Social Security and senior citizen health programs, as well as its opposition to the estate tax. The organization has been funded by Charles and David Koch. Although the organization did have ties to Koch family in the past, they say that there have been no contributions from anyone in the Koch network for well over a decade.
Substituted amphetamines are a class of compounds based upon the amphetamine structure; it includes all derivative compounds which are formed by replacing, or substituting, one or more hydrogen atoms in the amphetamine core structure with substituents. The compounds in this class span a variety of pharmacological subclasses, including stimulants, empathogens, and hallucinogens, among others. Examples of substituted amphetamines are amphetamine (itself), methamphetamine, ephedrine, cathinone, phentermine, mephentermine, tranylcypromine, bupropion, methoxyphenamine, selegiline, amfepramone (diethylpropion), pyrovalerone, MDMA (ecstasy), and DOM (STP).
Linaclotide, is a drug used to treat irritable bowel syndrome with constipation and chronic constipation with no known cause. It has a black box warning about the risk of serious dehydration in children in the US; the most common adverse effects in others include diarrhea.
MT-45 (IC-6) is an opioid analgesic drug invented in the 1970s by Dainippon Pharmaceutical Co. It is chemically a 1-substituted-4-(1,2-diphenylethyl) piperazine derivative, which is structurally unrelated to most other opioid drugs. Racemic MT-45 has around 80% the potency of morphine, with almost all opioid activity residing in the (S) enantiomer. It has been used as a lead compound from which a large family of potent opioid drugs have been developed, including full agonists, partial agonists, and antagonists at the three main opioid receptor subtypes. Fluorinated derivatives of MT-45 such as 2F-MT-45 are significantly more potent as μ-opioid receptor agonists, and one of its main metabolites 1,2-diphenylethylpiperazine also blocks NMDA receptors.
Teixobactin is a peptide-like secondary metabolite of some species of bacteria, that kills some gram-positive bacteria. It appears to belong to a new class of antibiotics, and harms bacteria by binding to lipid II and lipid III, important precursor molecules for forming the cell wall.
Cyclopentyne is a cycloalkyne containing five carbon atoms in the ring. Due to the ideal bond angle of 180° at each atom of the alkyne but the structural requirement that the bonds form a ring, this chemical is a highly strained structure, and the triple bond is highly reactive. The triple bond easily undergoes both [2+2] and [4+2] cycloaddition reactions. Unlike benzyne, which undergoes a [2+2] addition with loss of stereochemistry at the alkene partner, cyclopentyne reacts with alkenes with retention of geometry of the partner, an example of the relevance of orbital symmetry even for highly reactive structures. The structure can also form a π complex with lithium cations, which affects the cycloaddition reactivity. It can even interact strongly enough with copper species to form a novel type of metallacycle.
