The heterometallic complexes trans‐Cp(dppe)FeNCRu(o‐bpy)CNFe(dppe)CpPF6n (1PF6n, n=2, 3, 4; o‐bpy=1,2‐bis(2,2′‐bipyridyl‐6‐yl)ethane, dppe=1,2‐bis(diphenylphosphino)ethane, Cp=1,3‐cyclopentadiene) in ...three distinct states have been synthesized and fully characterized. 13+PF63 and 14+PF64 are the one‐ and two‐electron oxidation products of 12+PF62, respectively. The investigated results suggest that 1PF63 is a Class II mixed valence compound. 1PF64 after a thermal treatment at 400 K shows an unusually delocalized mixed valence state of FeIII‐NC‐RuIII‐CN‐FeII, which is induced by electron transfer from the central RuII to the terminal FeIII in 1PF64, which was confirmed by IR spectroscopy, magnetic data, and EPR and Mössbauer spectroscopy.
Heat to delocalize: Thermal activation at 400 K causes a localized diamagnetic cyanidometal‐bridged polynuclear compound FeIII‐NC‐RuII‐CN‐FeIII to transform into an unusually delocalized mixed‐valence state FeIII‐NC‐RuIII‐CN‐FeII.
Background
This study aimed to evaluate the role of baseline circulating tumor cells (CTCs) before and during concurrent chemoradiotherapy and attempted to determine the impacts of CTCs on the ...outcomes in patients with head and neck squamous cell carcinoma.
Methods
CTCs were detected using a negative selection strategy and flow cytometry protocol.
Results
We observed a significant correlation between baseline CTCs and staging (P = 0.001). The CTC counts were significantly reduced within 2‐4 weeks in 47 concurrent chemoradiotherapy responders (P < 0.001). Change of CTC counts correlates with progression‐free survival (PFS, P = 0.01) and overall survival (OS, P = 0.01). CTC decline status was an independent prognostic factor in PFS (P = 0.03) and OS (P = 0.05) in multivariate analyses.
Conclusion
In chemoradiotherapy responders, CTCs are significantly reduced. CTC decline within the first month indicates a longer PFS and OS, suggesting that the dynamics of CTCs could be more important than CTC number alone.
To investigate the effects of cis/trans‐configuration of the cyanidometal bridge and the electron donating ability of the auxiliary ligand on the cyanidometal bridge on metal to metal charge transfer ...(MMCT) in cyanidometal‐bridged mixed valence compounds, two groups of trinuclear cyanidometal‐bridged compounds cis/trans‐Cp(dppe)Fe(μ‐NC)Ru(4,4’‐dmbpy)2(μ‐CN)Fe(dppe)CpPF6n (n=2 (cis/trans‐1PF62), 3 (cis/trans‐1PF63), 4 (cis/trans‐1PF64)) and cis/trans‐Cp(dppe)Fe(μ‐NC)Ru(bpy)2(μ‐CN)Fe(dppe)CpPF63 (cis/trans‐2PF63) were synthesized and fully characterized. The experimental results indicate that for these one‐ and two‐electron oxidation mixed valence compounds, the trans‐configuration compounds are more beneficial for MMCT than the cis‐configuration compounds, and increasing the electron donating ability of the auxiliary ligand on the cyanidometal bridge is also conductive to MMCT. Moreover, compounds cis/trans‐1PF6n (n=3, 4) and cis/trans‐2PF63 belong to localized compounds by analyzing the experimental characterization results, supported by the TDDFT calculations.
Two series of trinuclear cyanidometal‐bridged compounds with cis/trans configuration were synthesized and fully characterized in this work. The experimental results show that the trans‐configuration and the ligand with high electron‐donating ability of the central cyanidometal bridge are more favorable for MMCT in trinuclear cyanidometal‐bridged mixed valence compounds, and these mixed valence compounds all belong to localized compounds, supported by the TDDFT calculations.
The two stable pairs of trimetallic compounds trans‐Cp*(dppe)Ru(μ‐NC)Ru(dmap)4(μ‐CN)Ru(dppe)Cp*PF6n (1PF6n, n=2, 3; Cp*=1,2,3,4,5‐pentamethylcyclopentadiene; dppe=1,2‐bis‐(diphenylphosphino)ethane; ...dmap= 4‐dimethylaminopyridine) and trans‐Cp*(dppe)Ru(μ‐CN)Ru(dmap)4(μ‐NC)Ru(dppe)Cp*PF6n (2PF6n, n=2, 3), which demonstrate cyanide/isocyanide isomerism, have been synthesized and fully characterized. 13+PF63 and 23+PF63 are the one‐electron oxidation products of 12+PF62 and 22+PF62, respectively. The results suggest that 1PF63 is a class III mixed valence compound, whereas 2PF63 might be an unusually symmetrical class II–III mixed valence compound composed of the two asymmetrical delocalized RuIII−NC−RuII mixed valence subunits.
Isomeric triruthenium mixed valence (MV) compounds 13+PF63 and 23+PF63 contain CN bridges with different orientations. Upon isomerization, compound 13+ undergoes a change in the orientation of its ligating CN groups and the electron density of the cyanidometal‐bridged MV complex becomes fully delocalized (class III). Compound 23+ is composed of two asymmetrically delocalized RuII−CN−RuIII units and it behaves like a class II–III cyanide‐bridged MV species.
The synthesis and characterization of Class II–III mixed valence complexes have been an interesting topic due to their special intermediate behaviour between localized and delocalized mixed valence ...complexes. To investigate the influence of the isocyanidometal bridge on metal‐to‐metal charge transfer (MMCT) properties, a family of new isocyanidometal‐bridged complexes and their one‐electron oxidation products cis‐Cp(dppe)Fe−CN−Ru(L)2‐NC−Fe(dppe)CpPF6n (n=2, 3) (Cp=1,3‐cyclopentadiene, dppe=1,2‐bis(diphenylphosphino)ethane, L=2,2’‐bipyridine (bpy, 1PF6n), 5,5’‐dimethyl‐2,2’‐bipyridyl (5,5’‐dmbpy, 2PF6n) and 4,4’‐dimethyl‐2,2’‐bipyridyl (4,4’‐dmbpy, 3PF6n)) have been synthesized and fully characterized. The experimental results suggest that all the one‐electron oxidation products may belong to Class II–III mixed valence complexes, supported by TDDFT calculations. With the change of the substituents of the bipyridyl ligand on the Ru centre from H, 5,5’‐dimethyl to 4,4’‐dimethyl, the energy of MMCT for the one‐electron oxidation complexes changes in the order: 13+<23+<33+, and that for the two‐electron oxidation complexes decreases in the order 14+>34+>24+. The potential splitting (ΔE1/2(2)) between the two terminal Fe centres for NPF62 are the largest potential splitting for the cyanido‐bridged complexes reported so far. This work shows that the smaller potential difference between the bridging and the terminal metal centres would result in the more delocalized mixed valence complex.
A series of new heterotrimetallic isocyanidometal‐bridged complexes were synthesized and characterized. The experimental results show that the MMCT energy and the degree of electron delocalization of isocyanidometal‐bridged mixed valence complexes can be tuned systematically by changing the auxiliary ligand on the bridging metal centre. The half‐wave potential splitting between the terminal Fe centres in these three unoxidized complexes are the largest potential splitting for the cyanido‐bridged complexes reported so far.
Soil water deficit seriously affects crop production, and soil arbuscular mycorrhizal fungi (AMF) enhance drought tolerance in crops by unclear mechanisms. Our study aimed to analyze changes in ...non-targeted metabolomics in roots of trifoliate orange (
Poncirus trifoliata
) seedlings under well-watered and soil drought after inoculation with
Rhizophagus intraradices
, with a focus on terpenoid profile. Root mycorrhizal fungal colonization varied from 70% under soil drought to 85% under soil well-watered, and shoot and root biomass was increased by AMF inoculation, independent of soil water regimes. A total of 643 secondary metabolites in roots were examined, and 210 and 105 differential metabolites were regulated by mycorrhizal fungi under normal water and drought stress, along with 88 and 17 metabolites being up-and down-regulated under drought conditions, respectively. KEGG annotation analysis of differential metabolites showed 38 and 36 metabolic pathways by mycorrhizal inoculation under normal water and drought stress conditions, respectively. Among them, 33 metabolic pathways for mycorrhization under drought stress included purine metabolism, pyrimidine metabolism, alanine, aspartate and glutamate metabolism, etc. We also identified 10 terpenoid substances, namely albiflorin, artemisinin (−)-camphor, capsanthin, β-caryophyllene, limonin, phytol, roseoside, sweroside, and α-terpineol. AMF colonization triggered the decline of almost all differential terpenoids, except for β-caryophyllene, which was up-regulated by mycorrhizas under drought, suggesting potential increase in volatile organic compounds to initiate plant defense responses. This study provided an overview of AMF-induced metabolites and metabolic pathways in plants under drought, focusing on the terpenoid profile.
Derived from our original nomogram study by using the risk variables from multivariable analyses in the derivation cohort of 1383 patients with extranodal NK/T-cell lymphoma, nasal-type (ENKTCL) who ...were mostly treated with anthracycline-based chemotherapy, we propose an easily used nomogram-revised risk index (NRI), validated it and compared with Ann Arbor staging, the International Prognostic Index (IPI), Korean Prognostic Index (KPI), and prognostic index of natural killer lymphoma (PINK) for overall survival (OS) prediction by examining calibration, discrimination, and decision curve analysis in a validation cohort of 1582 patients primarily treated with non-anthracycline-based chemotherapy. The calibration of the NRI showed satisfactory for predicting 3- and 5-year OS in the validation cohort. The Harrell's C-index and integrated Brier score (IBS) of the NRI for OS prediction demonstrated a better performance than that of the Ann Arbor staging system, IPI, KPI, and PINK. Decision curve analysis of the NRI also showed a superior outcome. The NRI is a promising tool for stratifying patients with ENKTCL into risk groups for designing clinical trials and for selecting appropriate individualized treatment.
A series of trimetallic cyanidometal‐bridged compounds MenCp(dppe)FeII‐(μ‐NC)‐RuII(MeOpy)4‐(μ‐CN)‐FeII(dppe)CpMen ‐ PF62 (NPF62, n=0, N =1; n=1, N=2; n=3, N=3; Cp=cyclopentadiene, ...dppe=1,2‐bis(diphenylphosphino)ethane, MeOpy=4‐methoxypyridine) and their one‐ and two‐electron oxidized compounds N3+ and N4+ were synthesized and characterized. Meanwhile, a series of corresponding linear cyanido‐bridged pentanuclear compounds MenCp(dppe)FeIII‐(μ‐NC)‐RuII(MeOpy)4‐(μ‐NC)‐AgI‐(μ‐CN)‐RuII(MeOpy)4‐(μ‐CN)‐FeIII(dppe)CpMenBF45 (MBF45, n=0, M=4; n=1, M=5; n=3, M=6) were also obtained and well characterized. The investigations suggest that in the trinuclear system there exists remote interaction between the two Fe centers, but no significant interactions exist across the central silver unit between the metals on the two sides of the silver center in the pentanuclear system. In both the trinuclear N4+ and the pentanuclear M5+ complexes, there exists the neighboring RuII→FeIII MM′CT transitions, and the MM'CT energy in the corresponding trinuclear system is higher than those in the pentanuclear system in which no remote metal‐metal interaction occurs. Meanwhile, as the substituted methyl groups on the cyclopentadiene increases, the redox potential of the ruthenium in the trinuclear N4+ series increases, but that in the pentanuclear M5+ complexes decreases.
In order to investigate the properties of metal to metal charge transfer (MMCT) influenced by the relative energy level between the bridging unit and the terminal unit, two groups of ...heterotrimetallic cyanido-metal-bridged complexes,
trans
-Cp(dppe)Fe-CN-Ru(MeOpy)
4
-NC-Fe(dppe)CpX
n
(
1X
n
;
n
= 2, 3, or 4; X = PF
6
or BF
4
) (Cp = cyclopentadiene, dppe = 1,2-bis(diphenylphosphino)ethane, MeOpy = 4-methoxypyridine) and Cp*(dppe)Fe-CN-Ru(MeOpy)
4
-NC-Fe(dppe)Cp* X
n
(
2X
n
; Cp* = 1,2,3,4,5-pentamethylcyclopentadiene;
n
= 2, 3, or 4; X = PF
6
or BF
4
) were synthesized and fully characterized. The crystallography data suggest different oxidation sites in the ground state for one-electron oxidation products
1
3+
and
2
3+
, and the electrochemical and Mössbauer spectra suggest that in the one-electron oxidation compounds
1
3+
, the charge is delocalized all along the trimetal backbone Fe-Ru-Fe, while in
2
3+
, the charge is rather delocalized between the two metal parts Fe-Ru. Further oxidation of
N
3+
gives
N
4+
(
N
= 1 or 2), during which a spin transfer towards the terminal units is observed in both series.
A substituent change from Cp to Cp* in cyanidometal bridged Fe-Ru-Fe complexes makes the one-electron oxidation products not only show a redox site change from Ru to Fe, but also exhibit a delocalization range change from Fe-Ru-Fe to Fe-Ru.
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