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Sponges are prolific sources of various natural products that have provided the chemical scaffolds for new drugs. The sponges of the genus Petrosia inhabit various regions and contain a variety of biologically active natural products such as polyacetylenes, sterols, meroterpenoids, and alkaloids. This review aims to provide a comprehensive summary of the chemical structures and biological activities of Petrosia metabolites covering a period of more than four decades (between 1978 and 2020). It is also described in this review that the major groups of metabolites from members of the genus Petrosia differed with latitude. The polyacetylenes were identified to be the most predominant metabolites in Petrosia sponges in temperate regions, while tropical Petrosia species were sources of a greater variety of metabolites, such as meroterpenoids, sterols, polyacetylenes, and alkaloids.

Live-cell Raman imaging based on bioorthogonal Raman probes with distinct signals in the cellular Raman-silent region (1800–2800 cm −1 ) has attracted great interest in recent years. We report here a class of water-soluble and biocompatible polydiacetylenes with intrinsic ultrastrong alkyne Raman signals that locate in this region for organelle-targeting live-cell Raman imaging. Using a host-guest topochemical polymerization strategy, we have synthesized a water-soluble and functionalizable master polydiacetylene, namely poly(deca-4,6-diynedioic acid) (PDDA), which possesses significantly enhanced (up to ~10 4 fold) alkyne vibration compared to conventional alkyne Raman probes. In addition, PDDA can be used as a general platform for multi-functional ultrastrong Raman probes. We achieve high quality live-cell stimulated Raman scattering imaging on the basis of modified PDDA. The polydiacetylene-based Raman probes represent ultrastrong intrinsic Raman imaging agents in the Raman-silent region (without any Raman enhancer), and the flexible functionalization of this material holds great promise for its potential diverse applications. Raman probes which operate in the cellular silent region are of interest for live cell imaging. Here, the authors report on the development of a water soluble polydiacetylene Raman probe with enhanced Raman signal in the silent region which can be functionalised for organelle targeting and demonstrate application.

Conductive organic polymers are most commonly generated from the oxidation or reduction of conjugated polymers. Although such conjugated polymers are typically viewed as modern materials, the earliest examples of these polymers date back to the early 19th century. The modern era of conjugated polymers began with the first reports of their conductive nature in the early 1960s. However, it was advances in the 1970s that brought particular focus to these materials with the first example of conductivity values in the metallic regime, for which the 2000 Nobel Prize in Chemistry was awarded to Hideki Shirakawa, Alan MacDiarmid, and Alan Heeger. Unfortunately, the historical narrative of these polymers is currently quite muddled in the primary literature, with various inaccuracies commonly propagated. In an effort to present a more accurate account as a resource for the field, the present report will review the first 150 years of the four primary parent polymers−polyaniline, polypyrrole, polyacetylene, and polythiophene, from their early origins in 1834 to their rapid development in the mid‐1980s. Conductive organic polymers, from the oxidation or reduction of conjugated polymers, are viewed as modern materials, yet conjugated polymers date back to the 19th century. Here, the first 150 years of polyaniline, polypyrrole, polyacetylene, and polythiophene are reviewed from their origins in 1834 to their rapid development in the mid‐1980s.

Chemical study of the CH2Cl2−MeOH (1:1) extract from the sponge Haliclona sp. collected in Mayotte highlighted three new long-chain highly oxygenated polyacetylenes, osirisynes G-I (1–3) together with the known osirisynes A (4), B (5), and E (6). Their structures were elucidated by 1D and 2D NMR spectra and HRESIMS and MS/MS data. All compounds were evaluated on catalase and sirtuin 1 activation and on CDK7, proteasome, Fyn kinase, tyrosinase, and elastase inhibition. Five compounds (1; 3–6) inhibited proteasome kinase and two compounds (5–6) inhibited CDK7 and Fyn kinase. Osirisyne B (5) was the most active compound with IC50 on FYNB kinase, CDK7 kinase, and proteasome inhibition of 18.44 µM, 9.13 µM, and 0.26 µM, respectively.

Conducting polymers (CPs) with high conductivity and solution processability have made great advances since the pioneering work on doped polyacetylene 1 – 3 , thus creating the new field of ‘organic synthetic metals, 4 . Various high-performance CPs have been realized, which enable the applications of several organic electronic devices 5 , 6 . Nevertheless, most CPs exhibit hole-dominant (p-type) transport behaviour 7 , 8 , whereas the development of n-type analogues lags far behind and only a few exhibit metallic state, typically limited by low doping efficiency and ambient instability. Here we present a facilely synthesized highly conductive n-type polymer poly(benzodifurandione) (PBFDO). The reaction combines oxidative polymerization and in situ reductive n-doping, greatly increasing the doping efficiency, and a doping level of almost 0.9 charges per repeating unit can be achieved. The resultant polymer exhibits a breakthrough conductivity of more than 2,000 S cm −1 with excellent stability and an unexpected solution processability without extra side chains or surfactants. Furthermore, detailed investigations on PBFDO show coherent charge-transport properties and existence of metallic state. The benchmark performances in electrochemical transistors and thermoelectric generators are further demonstrated, thus paving the way for application of the n-type CPs in organic electronics. A reaction is described combining oxidative polymerization and in situ reductive n-doping to yield poly(benzodifurandione), a facilely synthesized stable n-type conducting polymer with ultrahigh conductivity, with applications in organic electronics.

The developments of pure organic room-temperature phosphorescence (RTP) materials with circularly polarized luminescence (CPL) have significantly facilitated the future integration and systemization of luminescent material in fundamental science and technological applications. Here, a type of photoinduced circularly polarized RTP materials are constructed by homogeneously dispersing phosphorescent chiral helical substituted polyacetylenes into a processable poly(methyl methacrylate) (PMMA) matrix. These substituted polyacetylenes play vital roles in the propagation of CPL and present prominently optical characteristics with high absorption and luminescent dissymmetric factors up to 0.029 (g abs ) and 0.019 (g lum ). The oxygen consumption properties of the films under UV light irradiation endow materials with dynamic chiro-optical functionality, which can leverage of light to precisely control and manipulate the circularly polarized RTP properties with the remarkable advantages of being contactless, wireless and fatigue-resistant. Significantly, the distinct materials with dynamic properties can be used as anti-counterfeiting materials involving photoprogrammability. ‘Pure organic room-temperature phosphorescence (RTP) materials with circularly polarized luminescence (CPL) gained increasing interest. Here, the authors propose a photoinduced circularly polarized RTP material by homogeneously dispersing phosphorescent chiral polyacetylenes into a processable polymer matrix.

Lobetyolin (LBT) is a polyacetylene glycoside found in diverse medicinal plants but mainly isolated from the roots of Codonopsis pilosula, known as Radix Codonopsis or Dangshen. Twelve traditional Chinese medicinal preparations containing Radix Codonopsis were identified; they are generally used to tonify spleen and lung Qi and occasionally to treat cancer. Here we have reviewed the anticancer properties of Codonopsis extracts, LBT and structural analogs. Lobetyolin and lobetyolinin are the mono- and bis-glucosylated forms of the polyacetylenic compound lobetyol. Lobetyol and LBT have shown activities against several types of cancer (notably gastric cancer) and we examined the molecular basis of their activity. A down-regulation of glutamine metabolism by LBT has been evidenced, contributing to drug-induced apoptosis and tumor growth inhibition. LBT markedly reduces both mRNA and protein expression of the amino acid transporter Alanine-Serine-Cysteine Transporter 2 (ASCT2). Other potential targets are proposed here, based on the structural analogy with other anticancer compounds. LBT and related polyacetylene glycosides should be further considered as potential anticancer agents, but more work is needed to evaluate their efficacy, toxicity, and risk–benefit ratio.

Mushrooms have been attracting attention as a source of bioactive compounds for the development of dietary supplements and medicines. Many researchers have reported pharmacological effects of edible mushrooms, and have isolated and identified bioactive substances. Lentinula edodes (shiitake) and Flammulina velutipes (enokitake) are the cultivated edible mushrooms that are popular throughout the world. In L. edodes, polyacetylenes and sulfur compounds have been shown to display antimicrobial activity. In F. velutipes, many types of bioactive terpenes have been reported from mycelium culture filtrate or solid culture substrate. This article reviews the bioactive metabolites of low-molecular weight from L. edodes and F. velutipes.

Background Falcarinol-type polyacetylenes (PAs) such as falcarinol (FaOH) and falcarindiol (FaDOH) are produced by several Apiaceae vegetables such as carrot, parsnip, celeriac and parsley. They are known for numerous biological functions and contribute to the undesirable bitter off-taste of carrots and their products. Despite their interesting biological functions, the genetic basis of their structural diversity and function is widely unknown. A better understanding of the genetics of the PA levels present in carrot roots might support breeding of carrot cultivars with tailored PA levels for food production or nutraceuticals. Results A large carrot F 2 progeny derived from a cross of a cultivated inbred line with an inbred line derived from a Daucus carota ssp . commutatus accession rich in PAs was used for linkage mapping and quantitative trait locus (QTL) analysis. Ten QTLs for FaOH and FaDOH levels in roots were identified in the carrot genome. Major QTLs for FaOH and FaDOH with high LOD values of up to 40 were identified on chromosomes 4 and 9. To discover putative candidate genes from the plant fatty acid metabolism, we examined an extended version of the inventory of the carrot FATTY ACID DESATURASE2 ( FAD2 ) gene family. Additionally, we used the carrot genome sequence for a first inventory of ECERIFERUM1 ( CER1 ) genes possibly involved in PA biosynthesis. We identified genomic regions on different carrot chromosomes around the found QTLs that contain several FAD2 and CER1 genes within their 2-LOD confidence intervals. With regard to the major QTLs on chromosome 9 three putative CER1 decarbonylase gene models are proposed as candidate genes. Conclusion The present study increases the current knowledge on the genetics of PA accumulation in carrot roots. Our finding that carrot candidate genes from the fatty acid metabolism are significantly associated with major QTLs for both major PAs, will facilitate future functional gene studies and a further dissection of the genetic factors controlling PA accumulation. Characterization of such candidate genes will have a positive impact on carrot breeding programs aimed at both lowering or increasing PA concentrations in carrot roots.

Boundaries between distinct topological phases of matter support robust, yet exotic quantum states such as spin–momentum locked transport channels or Majorana fermions 1 – 3 . The idea of using such states in spintronic devices or as qubits in quantum information technology is a strong driver of current research in condensed matter physics 4 – 6 . The topological properties of quantum states have helped to explain the conductivity of doped trans -polyacetylene in terms of dispersionless soliton states 7 – 9 . In their seminal paper, Su, Schrieffer and Heeger (SSH) described these exotic quantum states using a one-dimensional tight-binding model 10 , 11 . Because the SSH model describes chiral topological insulators, charge fractionalization and spin–charge separation in one dimension, numerous efforts have been made to realize the SSH Hamiltonian in cold-atom, photonic and acoustic experimental configurations 12 – 14 . It is, however, desirable to rationally engineer topological electronic phases into stable and processable materials to exploit the corresponding quantum states. Here we present a flexible strategy based on atomically precise graphene nanoribbons to design robust nanomaterials exhibiting the valence electronic structures described by the SSH Hamiltonian 15 – 17 . We demonstrate the controlled periodic coupling of topological boundary states 18 at junctions of graphene nanoribbons with armchair edges to create quasi-one-dimensional trivial and non-trivial electronic quantum phases. This strategy has the potential to tune the bandwidth of the topological electronic bands close to the energy scale of proximity-induced spin–orbit coupling 19 or superconductivity 20 , and may allow the realization of Kitaev-like Hamiltonians 3 and Majorana-type end states 21 . Graphene nanoribbons are used to design robust nanomaterials with controlled periodic coupling of topological boundary states to create quasi-one-dimensional trivial and non-trivial electronic quantum phases.