This is a working overview of lyophilized, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-19 and is reviewed periodically as new material appears.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Calculated for the free peptide |
| Molecular weight | About 751.9 g/mol | Derived from the sequence |
| Appearance | White to off-white powder | Typical lyophilised form |
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Laudanum remains available by prescription in the United States (under the generic name "opium tincture") and in the European Union and United Kingdom (under the trade name Dropizol), although the drug's therapeutic indication is generally limited to controlling diarrhea when other medications have failed. The terms laudanum and tincture of opium are generally interchangeable, but in contemporary medical practice, the latter is used almost exclusively.
== History == Efficacy was evaluated in HERIZON-BTC-01 (NCT04466891), an open-label multicenter, single-arm trial in 62 participants with unresectable or metastatic HER2-positive (IHC3+) biliary tract cancer. Participants were required to have received at least one prior gemcitabine-containing regimen in the advanced disease setting. The US Food and Drug Administration (FDA) granted the application for zanidatamab priority review, breakthrough therapy, and orphan drug designations.
In chemistry, a molecule or ion is called chiral () if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes. This geometric property is called chirality (). The terms are derived from Ancient Greek χείρ (cheir) 'hand'; which is the canonical example of an object with this property. A chiral molecule or ion exists in two stereoisomers that are mirror images of each other, called enantiomers; they are often distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. The two enantiomers have the same chemical properties, except when reacting with other chiral compounds. They also have the same physical properties, except that they often have opposite optical activities. A homogeneous mixture of the two enantiomers in equal parts, a racemic mixture, differs chemically and physically from the pure enantiomers. Chiral molecules will usually have a stereogenic element from which chirality arises. The most common type of stereogenic element is a stereogenic center, or stereocenter. In the case of organic compounds, stereocenters most frequently take the form of a carbon atom with four distinct groups attached to it in a tetrahedral geometry. Less commonly, other atoms like N, P, S, and Si can also serve as stereocenters, provided they have four distinct substituents (including lone pair electrons) attached to them.
Savimbi used Jamba to augment UNITA's public image, investing heavily in local infrastructure. He opened the settlement to American and South African journalists, honed his public relations skills in frequent press conferences denouncing the MPLA, and lobbied for Western aid. Under the Reagan Doctrine, the US government opened covert channels to provide military assistance to UNITA. It repealed the Clark Amendment, which explicitly barred further CIA support for the UNITA and the FNLA, allowing the agency to resume Angolan operations. The Angolan government asserted this was "proof of the complicity there has always been between the US executive and the retrograde racist Pretoria regime" and it had "no alternative but to suspend the contacts it has had with US government envoys". In 1986, Savimbi visited Washington, where he met with American officials and was promised military hardware valued at about 10 million dollars, including FIM-92 Stinger surface-to-air missiles and BGM-71 TOW anti-tank missiles. The US also pledged to continue its support for UNITA even if it lost the umbrella of protection conferred by the SADF presence in southern Angola. At the US government's request, South Africa began lending UNITA a greater degree of material assistance, and aided the CIA in the acquisition of untraceable arms for the Angolan insurgents. The CIA was interested in acquiring Soviet and Eastern European arms for UNITA, as they could be easily passed off as weapons individual partisans had captured from FAPLA.
After several years of researching disgust, Jonathan Haidt, and others, studied its opposite; the term "elevation" was coined. Elevation is a pleasant moral emotion, triggered by witnessing virtuous acts of remarkable moral goodness and resulting in a desire to act morally and do "good". As an emotion it has a biological basis, and is sometimes characterized by a feeling of expansion in the chest or a tingling feeling on the skin.
Sources: en.wikipedia.org
As the price of bitcoin rose to $44,000 in December 2023, Bukele announced that El Salvador's investment into bitcoin had broken even. In March 2024, he stated that El Salvador had made a 50-percent profit from bitcoin. Bukele mocked news-media outlets on Twitter, saying that there were "literally thousands of articles" about El Salvador's bitcoin losses and the same outlets were now "totally silent". By 19 January 2025, the Salvadoran government had 6,043 bitcoins worth $611.2 million. In November 2021, Bukele announced that he planned to build Bitcoin City in the southeastern region of La Unión at the base of the Conchagua volcano. The city would use geothermal energy to power bitcoin mining. Ricardo Navarro, head of the Salvadoran Center of Appropriate Technology, criticized the plan, adding that it would result in an "environmental disaster". Bukele published images of models of Bitcoin City and its planned airport on Twitter in May 2022, saying that the city would have "no income tax, zero property tax, no procurement tax, zero city tax, and zero CO2 emissions". In December 2023, the Legislative Assembly passed a law that allowed individuals to purchase Salvadoran citizenship by donating bitcoins to El Salvador. On 18 December 2024, the International Monetary Fund (IMF) agreed to give El Salvador a $1.4 billion loan in exchange for the Salvadoran government making some concessions from the Bitcoin Law.
== Drug interactions == A significant interaction has also been recorded with allopurinol, and administration of these drugs together should be avoided. Reduction in indinavir and delavirdine plasma levels have been shown to occur when administered simultaneously with didanosine; these drugs should be administered at different times. Ketoconazole, itraconazole, ciprofloxacin should be administered at a different time from didanosine due to interactions with the buffering agent. Administration with drugs with overlapping toxicity, such as zalcitabine and stavudine, is not recommended. Alcohol can exacerbate didanosine's toxicity, and avoiding drinking alcohol while taking didanosine is recommended.
{\displaystyle {\begin{array}{l}{}\\{\ce {^{6}_{4}Be->[5\ {\ce {zs}}]{^{4}_{2}He}+{2_{1}^{1}H}}}\\{\ce {{^{7}_{4}Be}+e^{-}->[53.22\ {\ce {d}}]{^{7}_{3}Li}}}\\{\ce {^{8}_{4}Be->[81.9\ {\ce {as}}]{2_{2}^{4}He}}}\\{\ce {^{10}_{4}Be->[1.387\ {\ce {Ma}}]{^{10}_{5}B}+e^{-}}}\\{\ce {^{11}_{4}Be->[13.76\ {\ce {s}}]{^{11}_{5}B}+e^{-}}}\\{\ce {^{11}_{4}Be->[13.76\ {\ce {s}}]{^{7}_{3}Li}+{^{4}_{2}He}+e^{-}}}\\{\ce {^{12}_{4}Be->[21.46\ {\ce {ms}}]{^{12}_{5}B}+e^{-}}}\\{\ce {^{12}_{4}Be->[21.46\ {\ce {ms}}]{^{11}_{5}B}+{^{1}_{0}n}+e^{-}}}\\{\ce {^{13}_{4}Be->[1\ {\ce {zs}}]{^{12}_{4}Be}+{^{1}_{0}n}}}\\{\ce {^{14}_{4}Be->[4.53\ {\ce {ms}}]{^{13}_{5}B}+{^{1}_{0}n}+e^{-}}}\\{\ce {^{14}_{4}Be->[4.53\ {\ce {ms}}]{^{14}_{5}B}+e^{-}}}\\{\ce {^{14}_{4}Be->[4.53\ {\ce {ms}}]{^{12}_{5}B}+{2_{0}^{1}n}+e^{-}}}\\{\ce {^{15}_{4}Be->[790\ {\ce {ys}}]{^{14}_{4}Be}+{^{1}_{0}n}}}\\{}{\ce {^{16}_{4}Be->[650\ {\ce {ys}}]{^{14}_{4}Be}+{2_{0}^{1}n}}}\\{}\end{array}}}
Dulaglutide, sold under the brand name Trulicity, is a medication used for the treatment of type 2 diabetes in combination with diet and exercise. This medication is often prescribed for adults and children age 10 and older with type 2 diabetes (citation). It is utilized alongside diet and exercise in order to improve blood sugar. It is also approved in the United States for the reduction of major adverse cardiovascular events such as death, heart attack, or stroke in adults with type 2 diabetes who have established cardiovascular disease or multiple cardiovascular risk factors. It is not yet known if it is beneficial, safe, or effective in lowering blood sugar in children under 10 years of age. Trulicity is taken by giving an injection once a week under the skin of your stomach, thigh, or upper arm. The medication is a prescription that comes in the form of a pre-filled single-dose pen in 0.75mg, 1.5mg, 3mg, or 4.5mg per 5mg injection. You are able to take the dosage at any time during the day of administration with/without food eaten. The most common side effects upon administration are nausea, diarrhea, vomiting, abdominal pain, and decreased appetite. Dulaglutide injection is in a class of medications called incretin mimetics, as it is a glucagon-like peptide-1 receptor agonist (GLP-1 agonist) consisting of GLP-1(7-37) covalently linked to an Fc fragment of human IgG4. GLP-1 is a hormone that is involved in normalizing the level of glucose in blood (glycemia). It works by aiding the pancreas to release the correct amount of insulin when blood sugar levels are high.
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.
Selank is a synthetic analogue built on the tuftsin tetrapeptide Thr-Lys-Pro-Arg. Extra proline residues were added to the C-terminus during design work. That modification is intended to make the peptide less vulnerable to rapid enzymatic degradation.
Transliteration from Russian produces variant spellings such as Selanc. Many suppliers avoid the trade-style name entirely and list the peptide sequence. Comparing sequences rather than names is the reliable way to confirm two entries describe the same molecule.
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.