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Fluorinated cycloparaphenylenes (FCPPs) have attracted attention as electron-accepting CPPs as well as strained fluoroarenes. Herein, we report the synthesis and properties of novel FCPPs; F 16 [8]CPP and F 12 [6]CPP. Furthermore, the derivatization of F 16 [8]CPP afforded a new carbon nanoring where sixteen pyrrole rings are densely substituted on the CPP framework.

The active metal template (AMT) strategy is a powerful tool for the formation of mechanically interlocked molecules (MIMs) such as rotaxanes and catenanes, allowing the synthesis of a variety of MIMs, including π-conjugated and multicomponent macrocycles. Cycloparaphenylene (CPP) is an emerging molecule characterized by its cyclic π-conjugated structure and unique properties. Therefore, diverse modifications of CPPs are necessary for its wide application. However, most CPP modifications require early stage functionalization and the direct modification of CPPs is very limited. Herein, we report the synthesis of a catenane consisting of [9]CPP and a 2,2'-bipyridine macrocycle as a new CPP analogue that contains a reliable synthetic scaffold enabling diverse and concise post-modification. Following the AMT strategy, the [9]CPP-bipyridine catenane was successfully synthesized through Ni-mediated aryl-aryl coupling. Catalytic C-H borylation/cross-coupling and metal complexation of the bipyridine macrocycle moiety, an effective post-functionalization method, were also demonstrated with the [9]CPP-bipyridine catenane. Single-crystal X-ray structural analysis revealed that the [9]CPP-bipyridine catenane forms a tridentated complex with an Ag ion inside the CPP ring. This interaction significantly enhances the phosphorescence lifetime through improved intermolecular interactions., (© 2023 Wiley-VCH GmbH.)

Peripheral structural modifications of arenes are widely used to control or improve the optoelectronic properties, molecular assembly, and stability of aromatic π-materials as well as to explore new functions. However, known modifications are often tedious and complex; therefore, a simple yet powerful modification strategy is needed. We discovered that annulation with a simple adamantane scaffold exerts a significant impact on the properties, alignment, and stability of aromatic π-systems. This unprecedented adamantane annulation was achieved by a two-step transformation of metallated arenes and 4-protoadamantanone, generating a range of adamantane-annulated arenes. Analysis of structural and electronic properties uncovered unique effects of the process, such as high solubility and enhanced conjugation. The oxidation of adamantane-annulated perylenes produced strikingly stable cationic species with emission extended to the near-infrared region. This simple property modulation of aromatic π-systems would not only create potentially ground-breaking π-materials but also novel nanocarbon materials, such as diamond-graphene hybrids.

Perfluorinated aromatic compounds, the so-called perfluoroarenes, are widely used in materials science owing to their high electron affinity and characteristic intermolecular interactions. However, methods to synthesize highly strained perfluoroarenes are limited, which greatly limits their structural diversity. Herein, we report the synthesis and isolation of perfluorocycloparaphenylenes (PFCPPs) as a class of ring-shaped perfluoroarenes. Using macrocyclic nickel complexes, we succeeded in synthesizing PF[n]CPPs (n = 10, 12, 14, 16) in one-pot without noble metals. The molecular structures of PF[n]CPPs (n = 10, 12, 14) were determined by X-ray crystallography to confirm their tubular alignment. Photophysical and electrochemical measurements revealed that PF[n]CPPs (n = 10, 12, 14) exhibited wide HOMO-LUMO gaps, high reduction potentials, and strong phosphorescence at low temperature. PFCPPs are not only useful as electron-accepting organic materials but can also be used for accelerating the creation of topologically unique molecular nanocarbon materials., (© 2022. The Author(s).)

The synthesis of each of the cycloiptycene derivatives was achieved in one step from the (6,6)carbon nanobelt. It was revealed that the carbon nanobelt reacted as a diene in the Diels-Alder reaction with arynes and alkynes. The structures of all products were identified by X-ray crystallography to confirm that the Diels-Alder reactions took place at the six central benzene rings of the carbon nanobelt. DFT calculations indicated that the release of strain energy is the driving force to promote the Diels-Alder reaction. By using this method, we have successfully synthesized cyclotetracosiptycene, the largest iptycene ever synthesized., (This journal is © The Royal Society of Chemistry 2020.)

The glycopolymers for glycosaminoglycan mimic were synthesized, and the inhibitory effects of Alzheimer's β-secretase (BACE-1) were examined. The regio-selective sulfation was conducted on N-acetyl glucosamine (GlcNAc), and the acrylamide derivatives were synthesized with the consequent sulfated GlcNAc. The glycopolymers were synthesized with acrylamide using radical initiator. The glycopolymer with sulfated GlcNAc showed the strong inhibitory effect on BACE-1, and the inhibitory effects were dependent on the sulfation positions. Especially, glycopolymers carrying 3,4,6-O-sulfo-GlcNAc showed the strong inhibitory effect. The docking simulation suggested that glycopolymers bind to the active site of BACE-1., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

18-amino-4''-O-benzoyl-4'''-N-demethyl-18-deoxospiramycins were designed and synthesized. Synthetic strategy involved selective demethylation of the dimethylamino group in forosamine, benzoylation of the hydroxyl group at the C4'' position and reductive N-amination of the formyl group. Antibacterial characteristics of spiramycin derivatives were tested. The derivatives exhibited promising activity against drug-resistant bacterial strains.

There are many new nuclear methods in diagnosing cardiovascular disease. We present about 2 nuclear diagnosing methods. One is about 123I-BMIPP and the other 123I-MIBG. 123I-beta-methyl iodophenyl pentadecanoic acid(123I-BMIPP) is the tracer to evaluate the metabolism of a fatty acid of the heart. A combination of perfusion and fatty acid imagings indicates the recovery of cardiac wall motion can be expected in acute myocardial infarction in zones where 123I-BMIPP decreased uptake is greater than 201T1 perfusion defect. In angina pectoris, especially in unstable angina, 123I-BMIPP may be available to detect myocardial ischemia. 123I-meta-iodobenzylguanidine(123I-MIBG) is the trace that be able to assess the heart with sympathetic innervation. 123I-MIBG scintigraphy is a useful noninvasive method for the assessment of not only myocardial ischemia but also the degree of congestive heart failure. Also, it is a useful in assessment of beta-blocker therapy.

This study was aimed to make a new stable model of chronic hypertension by administration of a nitric oxide synthase inhibitor. L-Nw-nitroarginine methylester (NAME), and using this model, to investigate the roles of nitric oxide for the cardiovascular regulation. Male Wistar rats were implanted of osmotic pumps filled with saline (control group: n = 8), 0.2M NAME (low NAME group: n = 13) or 1M NAME (high NAME group: n = 12) intraperitoneally. After 4-week observation of blood pressure (BP) and heart rate (HR), blood concentrations of cathecholamine, active renin, L-arginine and L-Nw-nitroarginine were measured and histological changes in aorta and heart were examined. Age-matched SHRSP (n = 9) served as positive controls. BP elevated in the low NAME and high NAME group (113.9 +/- 3.1 to 144.0 +/- 4.4 mmHg, and 114.1 +/- 7.3 to 181.4 +/- 9.0 mmHg, respectively; mean +/- S.E.), while BP remained constant in the control group and SHRSP group (116.8 +/- 5.5 to 120.6 +/- 1.9 mmHg, 200.3 +/- 5.1 to 213.8 +/- 7.4 mmHg, respectively). HR in the low NAME and high NAME group rapidly decreased (not equal to 410 to not equal to 340 bpm) and then slowly returned to the control level. HR in the control group and SHRSP group remained constant (not equal to 420 and not equal to 450 bpm, respectively). Noradrenaline increased significantly in the high NAME group (0.21 +/- 0.03 ng/ml), and there were no significant changes in the control, low NAME and SHR group (0.13 +/- 0.02, 0.14 +/- 0.02, 0.15 +/- 0.03 ng/ml, respectively). Adrenaline, dopamine and active renin concentrations did not differ among 4 groups. Aortic wall/lumen area ratio in the high NAME group was similar to that in SHRSP group, in spite of its lower BP and shorter duration of hypertension compared with SHRSP. Left ventricular wall of the high NAME group was significantly thicker than that of SHRSP group. These findings suggest that, in addition to endothelium-derived NO, NO produced in the brain and peripheral neurons may function to regulate cardiovascular system by inhibiting noradrenaline release from sympathetic nerves or by inhibiting cardiac and vascular cell proliferation.

Effects on circulating blood volume (CBV) of the intravenous injection of a nonionic contrast medium, ioversol, with various doses were assessed in order to find a way of injection with less effects on systemic circulation. Ioversol was injected as a bolus to 20 mongrel dogs at doses of A: 3.75 ml/kg (n = 8) or B: 2 ml/kg (n = 6) of a solution containing 320 mg iodine per ml, or C: 2 ml/kg (n = 6) of a 240 mgI/ml solution. Colloid oncotic pressure (COP) of the bloods drawn before and 1, 2, 3, 5 min after the injection of ioversol was measured by a needle type osmometer, and changes in CBV were calculated using the COP values. Upon injection of ioversol CBV increased rapidly and then gradually returned to the preinjection levels. The change in CBV induced by ioversol was significantly less than those reportedly induced by an ionic contrant medium, iothalamate, and a nonionic medium, iopamidol, and comparable to that by another nonionic medium, iohexol. The degree of increase in CBV and the blood concentration of ioversol were related to the amount, but not the volume, of ioversol injected. Thus, ioversol proved to be one of the low osmotic nonionic contrast media with less effects on CBV. Furthermore, it is suggested that the amount, rather than volume, of contrast medium should be taken into consideration when the angiography of the patients with reduced cardiac function, children or aged patients is performed in whom the contrast medium-induced CBV expansion needs to be as less as possible.