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Gonane
Gonane is a chemical compound with formula , whose molecule can be described as three molecules or entities of cyclohexane and one of cyclopentane, fused in a particular way. More specifically, the molecule can be described as that of cycloheptadecane (–CH2–)17 with three extra bonds connecting carbons 1 to 13, 4 to 12, and 5 to 9, replacing six hydrogen atoms. It can also be viewed as the result of fusing a cyclopentane molecule with a fully hydrogenated molecule of phenanthrene, hence the more descriptive name perhydrocyclopenta henanthrene. Gonane is a tetracyclic hydrocarbon with no double bonds. It is formally the parent compound of the steroids; its carbon skeleton is called the "steroid nucleus". Some important gonane derivatives are the steroid hormones, characterized by methyl groups at the C10 and C13 positions and a side chain at the C17 position. Because gonane has six centers of chirality, it has 64 (26) theoretically possible stereoisomers, that differ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progestin
A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural product, natural female sex hormone progesterone in the body. A progestin is a ''synthetic compound, synthetic'' progestogen. Progestogens are used most commonly in hormonal contraception, hormonal birth control and menopausal hormone therapy. They can also be used in the treatment of gynecological conditions, to support fertility and pregnancy, to lower sex hormone levels for various purposes, and for other indications. Progestogens are used alone or in combination with estrogen (medication), estrogens. They are available in a wide variety of drug formulation, formulations and for use by many different route of administration, routes of administration. Examples of progestogens include natural or bioidentical progesterone (medication), progesterone as well as progestins such as medroxyprogesterone acetate and norethisterone. Side ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonanes
Gonane is a chemical compound with formula , whose molecule can be described as three molecules or entities of cyclohexane and one of cyclopentane, fused in a particular way. More specifically, the molecule can be described as that of cycloheptadecane (–CH2–)17 with three extra bonds connecting carbons 1 to 13, 4 to 12, and 5 to 9, replacing six hydrogen atoms. It can also be viewed as the result of fusing a cyclopentane molecule with a fully hydrogenated molecule of phenanthrene, hence the more descriptive name perhydrocyclopenta henanthrene. Gonane is a tetracyclic hydrocarbon with no double bonds. It is formally the parent compound of the steroids; its carbon skeleton is called the "steroid nucleus". Some important gonane derivatives are the steroid hormones, characterized by methyl groups at the C10 and C13 positions and a side chain at the C17 position. Because gonane has six centers of chirality, it has 64 (26) theoretically possible stereoisomers, that differ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levonorgestrel
Levonorgestrel is a hormonal medication which is used in a number of birth control methods. It is combined with an estrogen to make combination birth control pills. As an emergency birth control, sold under the brand name Plan B One-Step among others, it is useful within 72 hours of unprotected sex. The more time that has passed since sex, the less effective the medication becomes, and it does not work after pregnancy ( implantation) has occurred. Levonorgestrel works by preventing ovulation or fertilization from occurring. It decreases the chances of pregnancy by 57 to 93%. In an intrauterine device (IUD), such as Mirena among others, it is effective for the long-term prevention of pregnancy. A levonorgestrel-releasing implant is also available in some countries. Common side effects include nausea, breast tenderness, headaches, and increased, decreased, or irregular menstrual bleeding. When used as an emergency contraceptive, if pregnancy occurs, there is no evidence that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid
A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signaling molecules. Hundreds of steroids are found in plants, animals and fungi. All steroids are manufactured in cells from the sterols lanosterol (opisthokonts) or cycloartenol (plants). Lanosterol and cycloartenol are derived from the cyclization of the triterpene squalene. The steroid core structure is typically composed of seventeen carbon atoms, bonded in four " fused" rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring). Steroids vary by the functional groups attached to this four-ring core and by the oxidation state of the rings. Sterols are forms of steroids with a hydroxy group at position three and a skeleton derived from cholestane. ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pregnane
Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allopregnane) and 5β-pregnane (17β-ethyletiocholane). It has a gonane core. 5β-Pregnane is the parent of pregnanediones, pregnanolones, and pregnanediols, and is found largely in urine as a metabolic product of 5β-pregnane compounds. Pregnanes Pregnanes are steroid derivatives with carbons present at positions 1 through 21. Most biologically significant pregnane derivatives fall into one of two groups: pregnenes and pregnadienes. Another class is pregnatrienes. Pregnenes Pregnenes have a double bond. Examples include: * Cortisone * Hydrocortisone * Progesterone Pregnadienes Pregnadienes have two double bonds. Examples include: * Cyproterone acetate * Danazol * Fluocinonide See also * 5β-Pregnane * Pregnanedione * Pregna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androstane
Androstane is a C19 steroidal hydrocarbon with a gonane core. Androstane can exist as either of two isomers, known as 5α-androstane and 5β-androstane. File:androstane.png, 5α-Androstane File:androstane 5beta.png, 5β-Androstane Pharmacology 5α-Androstane is reported to be effective as an androgen, in spite of having no oxygen containing functional groups. See also * Estrane and pregnane * List of androstanes This is a list of androstanes, or androstane derivatives. Androstanes * Androstanol ** 3α,5α-Androstanol (5α-androstan-3α-ol) – an endogenous CAR antagonist ** 3α,5β-Androstanol (5α-androstan-3β-ol) – an endogenous CAR antagonist ... * C19H32 References {{Androgen receptor modulators Androgens and anabolic steroids Androstanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrane
Estrane is a C18 steroid derivative, with a gonane core. ''Estrenes'' are estrane derivatives that contain a double bond, with an example being nandrolone. ''Estratrienes'' (estrins) are estrane derivatives that contain three double bonds, for instance estrin (estra-1,3,5(10)-triene). The estrogen steroid hormones estradiol, estrone, and estriol are estra-1,3,5(10)-trienes. See also * Androstane * Pregnane Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allop ... References Estranes {{Steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrane
Estrane is a C18 steroid derivative, with a gonane core. ''Estrenes'' are estrane derivatives that contain a double bond, with an example being nandrolone. ''Estratrienes'' (estrins) are estrane derivatives that contain three double bonds, for instance estrin (estra-1,3,5(10)-triene). The estrogen steroid hormones estradiol, estrone, and estriol are estra-1,3,5(10)-trienes. See also * Androstane * Pregnane Pregnane, also known as 17β-ethylandrostane or as 10β,13β-dimethyl-17β-ethylgonane, is a C21 steroid and, indirectly, a parent of progesterone. It is a parent hydrocarbon for two series of steroids stemming from 5α-pregnane (originally allop ... References Estranes {{Steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclohexane
Cyclohexane is a cycloalkane with the molecular formula . Cyclohexane is non-polar. Cyclohexane is a colorless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon. Cyclohexyl () is the alkyl substituent of cyclohexane and is abbreviated Cy. Production Modern On an industrial scale, cyclohexane is produced by hydrogenation of benzene in the presence of a Raney nickel catalyst. Producers of cyclohexane account for approximately 11.4% of global demand for benzene. The reaction is highly exothermic, with ΔH(500 K) = -216.37 kJ/mol. Dehydrogenation commenced noticeably above 300 °C, reflecting the favorable entropy for dehydrogenation. : Early Unlike benzene, cyclohexane is not found in natural resources such as coal. For this reason, early investigators synthesized their cyclohexane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Analog
A structural analog (analogue in modern traditional English; Commonwealth English), also known as a chemical analog or simply an analog, is a compound having a structure similar to that of another compound, but differing from it in respect to a certain component. It can differ in one or more atoms, functional groups, or substructures, which are replaced with other atoms, groups, or substructures. A structural analog can be imagined to be formed, at least theoretically, from the other compound. Structural analogs are often isoelectronic. Despite a high chemical similarity, structural analogs are not necessarily functional analogs and can have very different physical, chemical, biochemical, or pharmacological properties. In drug discovery, either a large series of structural analogs of an initial lead compound are created and tested as part of a structure–activity relationship study or a database is screened for structural analogs of a lead compound. Chemical analogues of il ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Group
In organic chemistry, an ethyl group (abbr. Et) is an alkyl substituent with the formula , derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry's nomenclature of organic chemistry for a saturated two-carbon moiety in a molecule, while the prefix "''eth-''" is used to indicate the presence of two carbon atoms in the molecule. Ethylation Ethylation is the formation of a compound by introduction of the ethyl group. The most widely practiced example of this reaction is the ethylation of benzene with ethylene to yield ethylbenzene, a precursor to styrene, which is a precursor to polystyrene. Approximately 24.7 million tons of ethylbenzene were produced in 1999. :: Many ethyl-containing compounds are generated by electrophilic ethylation, i.e. treatment of nucleophiles with sources of Et+. Triethyloxonium tetrafluoroborate t3OF4 is such a reagent. For good nucleophiles, less electrophilic reagents are employed, such as ethyl h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
