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Photochemical approaches afford high spatiotemporal control over molecular structure and function, for broad applications in materials and biological science. Here, we present the first example of a visible light responsive ruthenium-based photolinker, Ru(bipyridine)2(3-ethynylpyridine)2 (RuBEP), which was reacted stoichiometrically with a 25mer DNA or morpholino (MO) oligonucleotide functionalized with 3′ and 5′ terminal azides, via Cu(i)-mediated [3+2] Huisgen cycloaddition reactions. RuBEP-caged circular morpholinos (Ru-MOs) targeting two early developmental zebrafish genes, chordin and notail, were synthesized and tested in vivo. One-cell-stage zebrafish embryos microinjected with Ru-MO and incubated in the dark for 24 h developed normally, consistent with caging, whereas irradiation at 450 nm dissociated one 3-ethynylpyridine ligand (Φ = 0.33) and uncaged the MO to achieve gene knockdown. As demonstrated, Ru photolinkers provide a versatile method for controlling structure and function of biopolymers.  相似文献   
84.
The olive tree (Olea europaea L.) can be affected by Colletotrichum acutatum, causing a loss of yield and quality of the final products, whilst the incidence of this fungal infection depends on several factors, including cultivar susceptibility. Thus, the effect of C. acutatum infection in cultivars displaying different susceptibilities to this fungal disease (‘Galega Vulgar’ ‐ susceptible, ‘Cobrançosa’ ‐ moderately susceptible, ‘Picual’ ‐ tolerant) has been assessed through spectrophotometric methods and HPLC, while the FTIR spectra of the cuticles have been concomitantly registered, resorting to the ATR accessory. With the support of multivariate analysis, these spectra allowed to discriminate olives with distinct infection times, besides retrieving evidences concerning the different susceptibility of each cultivar, while these observations were reinforced by the spectrophotometric and chromatographic methods. Furthermore, the assessment of the phenolic profile evidenced individual compounds in the distinct cultivars, so as their variations in response to the fungal infection.  相似文献   
85.
Russian Journal of Applied Chemistry - An increase in the production and consumption of polyurethane products used in heavy and light industry, in the construction industry, automotive, medicine,...  相似文献   
86.
Russian Journal of Organic Chemistry - A new series of 4-(1H-imidazol-4-yl)-2-(substituted phenyl)-1,4-dihydrobenzo[4,5]imidazo[1,2-a]­pyrimidines have been synthesized via a one-pot reaction...  相似文献   
87.
Russian Journal of Organic Chemistry - The reactivities of the L-Tyr–L-Pro dipeptide and its analog with a hydroxymethyl group instead of carboxy group in the proline moiety were compared by...  相似文献   
88.
Russian Chemical Bulletin - The reaction pyridoxal 5′-phosphate with resorcinols in EtOH in the presence of concentrated HCl gives hydrochlorides of the corresponding...  相似文献   
89.
Russian Chemical Bulletin - Nucleophilic substitution of the chlorine atom in 4,5-dichloro-1,2-dithiol-3-one using 1-thio-β-d-glucopyranose and its 2,3,4,6-tetra-O-acetyl derivative in...  相似文献   
90.
Russian Journal of Electrochemistry - The reduction of zinc oxide in a limited volume of the alkaline electrolyte is studied. Methods of chronopotentiometry, chronoamperometry, and...  相似文献   
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