The Kornblum–DeLaMare rearrangement is a rearrangement reaction in organic chemistry in which a primary or secondary organic peroxide is converted to the corresponding ketone and alcohol under acid or base catalysis. The reaction is relevant as a tool in organic synthesis and is a key step in the biosynthesis of prostaglandins.
Cryptophycins are a family of macrolide molecules that are potent cytotoxins and have been studied for potential antiproliferative properties useful in developing chemotherapy. They are members of the depsipeptide family.
Ageliferin is a chemical compound produced by some sponges. It was first isolated from Caribbean and then Okinawan marine sponges in the genus Agelas. It often co-exists with the related compound sceptrin and other similar compounds. It has antibacterial properties and can cause biofilms to dissolve.
The Petrenko-Kritschenko reaction is a classic multicomponent-name reaction that is closely related to the Robinson–Schöpf tropinone synthesis, but was published 12 years earlier.
Pinitol is a cyclitol, a cyclic polyol. It is a known anti-diabetic agent isolated from Sutherlandia frutescens leaves. Gall plant tannins can be differentiated by their content of pinitol. It was first identified in the sugar pine. It is also found in other plants, such as in the pods of the carob tree.
3-Alkylpyridinium (3-AP) compounds are natural chemical compounds that are found in marine sponges belonging to the order Haplosclerida. Some polymers derived from 3-APs are anticholinesterase agents and show hemolytic and cytotoxic activities. More than 70 structurally different 3-APs have been isolated from marine sponges. However, not all such sponges contain 3-AP compounds. Variation in content of 3-APs has been detected even within a single sponge species collected from different geographical area. Although 3-APs look structurally quite simple, the structure elucidation by NMR spectroscopy is complicated by the fact that most of the methylene groups in the alkyl chains show the same chemical shift. Therefore, the 3-APs are an ideal test case for a combined approach of NMR spectroscopy and mass spectrometry.
Callystatin A is a polyketide natural product from the leptomycin family of secondary metabolites. It was first isolated in 1997 from the marine sponge Callyspongia truncata which was collected from the Goto Islands in the Nagasaki Prefecture of Japan by the Kobayashi group. Since then its absolute configuration has been elucidated and callystatin A was discovered to have anti-fungal and anti-tumor activities with extreme potency against the human epidermoid carcinoma KB cells (IG50 = 10 pg/ml) and the mouse lymphocytic leukemia Ll210 cells (IG50 = 20 pg/ml).
Plakevulin A is a bio-active metabolite of the sea sponge Plakortis.
Suberedamines are bio-active isolates of Suberea, a marine sponge. The compounds are brominated tyrosine dimer derivatives.
Stevensine is a bromopyrrole alkaloid originally isolated from an unidentified Micronesian marine sponge, as well as a New Caledonian sponge, Pseudaxinyssa cantharella and Axinella corrugata. Total synthesis of stevensine has been achieved by Ying-zi Xu et al., and investigations into the biosynthetic origin has been explored by Paul Andrade et al. Understanding methods to synthesize stevensine and other similar compounds is an important step to accomplish, as marine sponges contain numerous biologically active metabolites that have been shown to function as anything from antitumor to antibacterial agents when tested for medicinal applications. Reasons for why marine sponges contain so many bio-active chemicals has been attributed to their sessile nature, and the need to produce chemical defenses to ensure survival. However, since many of these compounds naturally occur in small amounts, harvesting the sponges has in the past led to near-extinction of some species.
Affinine is a monoterpenoid indole alkaloid which can be isolated from plants of the genus Tabernaemontana. Structurally it can be considered a member of the vobasine alkaloid family and may be synthesized from tryptophan. Limited pharmacological testing has indicated that it may be an effective inhibitor of both acetylcholinesterase and butyrylcholinesterase.
Affinisine is a monoterpenoid indole alkaloid which can be isolated from plants of the genus Tabernaemontana. Structurally, it can be considered a member of the sarpagine alkaloid family and may be synthesized from tryptophan via a Pictet-Spengler reaction.
Lacking an immune system, protective shell, or mobility, sponges have developed an ability to synthesize a variety of unusual compounds for survival. C-nucleosides isolated from Caribbean Cryptotethya crypta, were the basis for the synthesis of zidovudine (AZT), aciclovir (Cyclovir), cytarabine (Depocyt), and cytarabine derivative gemcitabine (Gemzar).
Onnamide A is a bioactive natural product found in Theonella swinhoei, a species of marine sponge whose genus is well known for yielding a diverse set of biologically active natural products, including the swinholides and polytheonamides. It bears structural similarities to the pederins, a family of compounds known to inhibit protein synthesis in eukaryotic cells. Onnamide A and its analogues have attracted academic interest due to their cytotoxicity and potential for combating the growth and proliferation of cancer cells.
Dysidea arenaria is a species of marine sponge (poriferan) found in the Pacific Ocean. It is a member of the order Dictyoceratida, one of two sponge orders that make up the keratose or "horny" sponges in which a mineral skeleton is absent and a skeleton of organic fibers is present instead.
Swinholides are dimeric 42 carbon-ring polyketides that exhibit a 2-fold axis of symmetry. Found mostly in the marine sponge Theonella, swinholides encompass cytotoxic and antifungal activities via disruption of the actin skeleton. Swinholides were first described in 1985 and the structure and stereochemistry were updated in 1989 and 1990, respectively. Thirteen swinholides have been described in the literature, including close structural compounds such as misakinolides/bistheonellides, ankaraholides, and hurgholide A It is suspected that symbiotic microbes that inhabit the sponges rather than the sponges themselves produce swinholides since the highest concentration of swinholides are found in the unicellular bacterial fraction of sponges and not in the sponge fraction or cyanobacteria fraction that also inhabit the sponges.
Luffariella is a genus of sea sponges in the family Thorectidae.
1,2-Dioxolane is a chemical compound with formula C3H6O2, consisting of a ring of three carbon atoms and two oxygen atoms in adjacent positions. Its condensed structural formula is [–(CH
2)3–O–O–].
Fascaplysin is a marine alkaloid based on 12H-pyrido[1–2-a:3,4-b′]diindole ring system. It was first isolated as a red pigment from the marine sponge Fascaplysinopsis bergquist collected in the South Pacific near Fiji in 1988. Fascaplysin possesses a broad range of in vitro biological activities including analgesic, antimicrobial, antifungal, antiviral, antimalarial, anti-angiogenic, and antiproliferative activity against numerous cancer cell lines.
Plakortis is a genus of marine sponges in the order Homosclerophorida, first described by Franz Eilhard Schulze in 1880.
