Molecular Complexes and their Spectra. VIII. The Molecular Complex between Iodine and Triethylamine1

1958 ◽  
Vol 80 (3) ◽  
pp. 520-524 ◽  
Author(s):  
S. Nagakura
Keyword(s):  
Molecular Complex ◽  
Molecular Complexes

scholarly journals Polymer Optical Waveguide Sensor Based on Fe-Amino-Triazole Complex Molecular Switches

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 195
Author(s):  
Muhammad Shaukat Khan ◽  
Hunain Farooq ◽  
Christopher Wittmund ◽  
Stephen Klimke ◽  
Roland Lachmayer ◽  
...  
Keyword(s):  
Molecular Complex ◽  
Electromagnetic Interference ◽  
Optical Power ◽  
Uv Curing ◽  
Molecular Complexes ◽  
Core Material ◽  
Absorption Bands ◽  
Electronic Temperature ◽  
Polymer Waveguide ◽  
Temperature Detection

We report on a polymer-waveguide-based temperature sensing system relying on switchable molecular complexes. The polymer waveguide cladding is fabricated using a maskless lithographic optical system and replicated onto polymer material (i.e., PMMA) using a hot embossing device. An iron-amino-triazole molecular complex material (i.e., [Fe(Htrz)2.85(NH2-trz)0.15](ClO4)2) is used to sense changes in ambient temperature. For this purpose, the core of the waveguide is filled with a mixture of core material (NOA68), and the molecular complex using doctor blading and UV curing is applied for solidification. The absorption spectrum of the molecular complex in the UV/VIS light range features two prominent absorption bands in the low-spin state. As temperature approaches room temperature, a spin-crossover transition occurs, and the molecular complex changes its color (i.e. spectral properties) from violet-pink to white. The measurement of the optical power transmitted through the waveguide as a function of temperature exhibits a memory effect with a hysteresis width of approx. 12 °C and sensitivity of 0.08 mW/°C. This enables optical rather than electronic temperature detection in environments where electromagnetic interference might influence the measurements.

Unusual molecular complexes of antimony fluoride dimers with Acetonitrile and Pyridine: structures and bonding

2021 ◽  
Author(s):  
Elena I. Davydova ◽  
Alexander Viktorovich Virovets ◽  
Eugenia V. Presypkina ◽  
Anna Vladimirovna Pomogaeva ◽  
Anna S Lisovenko ◽  
...  
Keyword(s):  
Molecular Complex ◽  
Molecular Complexes ◽  
Antimony Pentafluoride ◽  
Antimony Trifluoride

Structures of two new molecular complexes of antimony pentafluoride with pyridine (Py) and acetonitrile (AN), SbF5•Py and Sb2F10•AN, as well as a molecular complex of antimony trifluoride Sb2F6•Py and its...

Estimation of the fraction of dative structure in molecular complexes using Hammett ρ values

1979 ◽  
Vol 57 (12) ◽  
pp. 1418-1420
Author(s):  
Bo-Long Poh
Keyword(s):  
Charge Transfer ◽  
Ionization Potential ◽  
Molecular Complex ◽  
Physical Interpretation ◽  
Molecular Complexes ◽  
Transfer Energy ◽  
Simple Method ◽  
Charge Transfer Energy

A simple method of estimating the fraction of dative structure in molecular complexes using Hammett ρ values is given. A physical interpretation of the parameter m in the equation, hν = mID + n, relating the charge-transfer energy, hν, of a molecular complex and the ionization potential, ID, of the donor is given.

scholarly journals The versatile molecular complex component LC8 promotes several distinct steps of flagellar assembly

2012 ◽  
Vol 198 (1) ◽  
pp. 115-126 ◽  
Author(s):  
Anjali Gupta ◽  
Dennis R. Diener ◽  
Priyanka Sivadas ◽  
Joel L. Rosenbaum ◽  
Pinfen Yang
Keyword(s):  
Molecular Complex ◽  
Binding Sites ◽  
Molecular Complexes ◽  
Terminal Region ◽  
Radial Spoke ◽  
Complex Component ◽  
Flagellar Assembly ◽  
A Subunit ◽  
Docking Proteins ◽  
Base Formation

LC8 is present in various molecular complexes. However, its role in these complexes remains unclear. We discovered that although LC8 is a subunit of the radial spoke (RS) complex in Chlamydomonas flagella, it was undetectable in the RS precursor that is converted into the mature RS at the tip of elongating axonemes. Interestingly, LC8 dimers bound in tandem to the N-terminal region of a spoke phosphoprotein, RS protein 3 (RSP3), that docks RSs to axonemes. LC8 enhanced the binding of RSP3 N-terminal fragments to purified axonemes. Likewise, the N-terminal fragments extracted from axonemes contained LC8 and putative spoke-docking proteins. Lastly, perturbations of RSP3’s LC8-binding sites resulted in asynchronous flagella with hypophosphorylated RSP3 and defective associations between LC8, RSs, and axonemes. We propose that at the tip of flagella, an array of LC8 dimers binds to RSP3 in RS precursors, triggering phosphorylation, stalk base formation, and axoneme targeting. These multiple effects shed new light on fundamental questions about LC8-containing complexes and axoneme assembly.

scholarly journals The Mode of SN38 Derivatives Interacting with Nicked DNA Mimics Biological Targeting of Topo I Poisons

2021 ◽  
Vol 22 (14) ◽  
pp. 7471
Author(s):  
Wojciech Bocian ◽  
Beata Naumczuk ◽  
Magdalena Urbanowicz ◽  
Jerzy Sitkowski ◽  
Anna Bierczyńska–Krzysik ◽  
...  
Keyword(s):  
Molecular Complex ◽  
Topoisomerase I ◽  
Molecular Complexes ◽  
Development Stage ◽  
Alkylation Reaction ◽  
Noesy Spectrum ◽  
Dna Duplexes ◽  
Preclinical Development ◽  
Nitrogen Bases ◽  
Biological Target

The compounds 7-ethyl-9-(N-methylamino)methyl-10-hydroxycamptothecin (2) and 7-ethyl-9-(N-morpholino)methyl-10-hydroxycamptothecin (3) are potential topoisomerase I poisons. Moreover, they were shown to have favorable anti-neoplastic effects on several tumor cell lines. Due to these properties, the compounds are being considered for advancement to the preclinical development stage. To gain better insights into the molecular mechanism with the biological target, here, we conducted an investigation into their interactions with model nicked DNA (1) using different techniques. In this work, we observed the complexity of the mechanism of action of the compounds 2 and 3, in addition to their decomposition products: compound 4 and SN38. Using DOSY experiments, evidence of the formation of strongly bonded molecular complexes of SN38 derivatives with DNA duplexes was provided. The molecular modeling based on cross-peaks from the NOESY spectrum also allowed us to assign the geometry of a molecular complex of DNA with compound 2. Confirmation of the alkylation reaction of both compounds was obtained using MALDI–MS. Additionally, in the case of 3, alkylation was confirmed in the recording of cross-peaks in the 1H/13C HSQC spectrum of 13C-enriched compound 3. In this work, we showed that the studied compounds—parent compounds 2 and 3, and their potential metabolite 4 and SN38—interact inside the nick of 1, either forming the molecular complex or alkylating the DNA nitrogen bases. In order to confirm the influence of the studied compounds on the topoisomerase I relaxation activity of supercoiled DNA, the test was performed based upon the measurement of the fluorescence of DNA stain which can differentiate between supercoiled and relaxed DNA. The presented results confirmed that studied SN38 derivatives effectively block DNA relaxation mediated by Topo I, which means that they stop the machinery of Topo I activity.

Evidence for molecular complexes in the mechanism of additions of iodine mono-chloride to alkenes

1984 ◽  
Vol 62 (11) ◽  
pp. 2526-2534 ◽  
Author(s):  
George H. Sçhmid ◽  
James W. Gordon
Keyword(s):  
Absorption Band ◽  
Equilibrium Constant ◽  
Molecular Complex ◽  
Molecular Complexes ◽  
Electrophilic Addition ◽  
Reaction Coordinate ◽  
Rate Law ◽  
Rate Determining Step ◽  
Enthalpy Changes ◽  
Enthalpy Of Activation

Immediately upon mixing ICls and 2,3-dimethyl-2-butene in CCl4 at 25 °C a new absorption band due to an alkene–ICl molecular complex appears at 295 ± 5 nm and decreases rapidly with time. The rate law under conditions of (alkene)0 [Formula: see text] (ICl)0 for the electrophilic addition of ICl to 2,3-dimethyl-2-butene, E- and Z-2-butene, and E- and Z-1-phenylpropene is −d(ICl)/dt = kexpt(alkene)(ICl)3/{1 + kAD(alkene)}3 where KAD is the equilibrium constant for the formation of a 1:1 alkene–ICl molecular complex. The addition of ICl to the Z and E isomers of 2-butene and 1-phenylpropene occurs by anti-stereospecific addition. The negative enthalpy of activation for the addition of ICl to 2,3-dimethyl-2-butene is evidence that one or more complexes are involved on the reaction coordinate prior to the rate-determining step. On the basis of analysis of the enthalpy changes during the reaction, it is proposed that both a 1:1 and a 1:2 alkene–ICl molecular complex is involved in the mechanism prior to the rate-determining step.

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