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The synthesis and study of the lanthanide luminescent 2,3-bis(1,2,3- triazol-4-yl)picolinamide (btp) based hydrogels F1 and F2 is described where Tb(iii) or Eu(iii) are also used to crosslink the btp units within the polymers.

The synthesis of chiral α-amino acid derived (1,2,3-triazol-4-yl)-picolinamide (tzpa) ligands 4–6 designed by combining the coordination properties of two well-known ligand structures within a single unit is described.

Bis-tridentate (1,2,3-triazol-4-yl)picolinamide (tzpa) was used to form Tb(iii) double- and triple-stranded di-metallic helicates in solution, where changes in the absorption and the Tb(iii) emission were used to monitor the formation of these supramolecular systems.

The synthesis of two new green emitting polymers, made by reacting the btp ligand 1 with the commercially available P(E-alt-MA) polymer and cross-linking with Tb(iii), is described.

A new flexible and divergent 1,2,3-triazol-4-yl-picolinamide (tzpa) ligand 2 and the half-equivalent model ligand 1, both functionalised with pendant 3-pyridyl groups, are reported and their coordination behaviour with silver(i) ions is explored, both in the crystalline phase and through the formation of a supramolecular metallogel. The self-assembly of tzpa ligand 1 with AgCF3SO3 resulted in the formation of a 1D coordination polymer, binding in a bidentate fashion through the pyridyl and triazole nitrogen atoms of the tzpa binding site and a pendant pyridyl nitrogen atom of an adjacent ligand. Doubling the number of metal binding sites in ligand 2, while retaining the same metal binding domain, gives rise to the formation of a supramolecular metallogel on reaction with AgBF4 at 5 wt% in MeCN, possessing self-healing properties.

Introduction Throughout the COVID-19 pandemic we conducted virtual urology clinics for the first time at our institution. We aimed to assess patient satisfaction with the virtual clinic format. Method Patients who underwent virtual consultation were contacted by phone and surveyed about their appointment. Convenience, thoroughness, satisfaction, preference and reason for appointment were assessed via questionnaire Results 77 randomly selected patients were contacted. 63 males (82%), 14 females (18%). Median age 61 years (range 16–86). 62 (80%) reviews, 12 (16%) new referrals, and 3 (4%) post-operative patients were surveyed. 55 (71%) were booked for repeat appointment, 13 (17%) for further investigations, 6 (8%) discharged, and 3 (4%) listed for surgery. 73 (95%) found it convenient, 3 (4%) were neutral and 1 (1%) found it inconvenient. 74 (96%) felt thoroughly assessed and 76 (99%) of patients had all their concerns addressed. 74 (96%) were satisfied with their review, 2 (3%) were neutral, and 1 (1%) was dissatisfied. Going forward, 50 (65%) would prefer virtual follow-up and 27 (35%) would prefer an in-person review. Conclusions Virtual clinic is preferable to the majority of patients in our urology service and is deemed convenient, thorough and satisfactory by them. It should be facilitated going forward in appropriately selected patients.

The btp [2,6-bis(1,2,3-triazol-4-yl)pyridine] ligand is a terdentate ligand that, analogously to many other terdentate ligands such as 2,2′;6,2″-terpyridine (terpy), has been shown to effectively bind to cationic metals through the central pyridyl nitrogen atom and through the triazolyl nitrogen atoms; however, in contrast to such classical ligands, btps also possess a unique capacity to bind to anions as well. Polarisation of the hydrogen atoms of the triazole rings allows them to form strong hydrogen bonding interactions with both anionic guests and with other btps through self-association. This dual binding property has seen the btp motif extended beyond traditional coordination chemistry applications to wider areas of contemporary interest, particularly in supramolecular chemistry. Thus, this review focuses initially on developments in btp coordination chemistry, discussing the use of this ligand with different metal ions, from transition metals to lanthanides and actinides. Then the second half of this review discusses ‘all-organic’ and supramolecular applications of this motif, where more unusual applications of this motif are explored, ranging from medicinal and optoelectronic applications to anion binding macrocycles and helicates, and mechanically interlocked molecules. We conclude by discussing potential future avenues of exploration for this highly exciting molecular building block.

The synthesis of a chiral bis-tridentate (1,2,3-triazol-4-yl)-picolinamide (tzpa) ligand is described and its coordination chemistry with Cu(NO3)2 and [Cu(MeCN)4]PF6 is explored in the crystalline phase as well as in solution. Chiral [2 × 2] tetranuclear square grid complexes [Cu4(H21)4](NO3)8 and [Cu4(H1)4](PF6)4 were observed, and crystallographically analysed, these being linkage isomers with N4O2 and N5O coordination spheres, respectively. These come about by an unusual in situ amide deprotonation and coordination, which accompanies a CuI → CuII oxidation process.

Introduction: During the COVID-19 pandemic we conducted virtual telephone clinics in lieu of physical clinics for the first time at our institution This study aims to assess patient satisfaction with the virtual clinic format Methods: Patients who underwent telephone virtual urology consultation were contacted subsequently by phone and surveyed on satisfaction of their virtual review Convenience, thoroughness, satisfaction and preference were assessed via questionnaire, as well as reason for review Results: 77 randomly selected patients were contacted, comprising 63 males (82%) and 14 females (18%) with a median age of 61 years (range 16–86) 62 (80%) reviews, 12 (16%) new referrals and 3 (4%) initial post-operative follow-up patients were surveyed 55 (71%) were booked for further outpatient review, 13 (17%) had further investigations arranged, 6 (8%) were discharged, and 3 (4%) were listed for surgery The majority of patients, 73 (95%), felt it was a convenient way to conduct clinic, 3 (4%) were neutral and 1 (1%) found it inconvenient 74 (96%) felt they were thoroughly assessed and 76 (99%) of patients had their concerns addressed 74 (96%) were satisfied with their phone consultation, 2 (3%) were neutral, and 1 (1%) was dissatisfied Going forward, 50 (65%) would prefer phone follow-up and 27 (35%) would prefer a physical appointment Conclusion: A virtual telephone clinic is preferable to the majority of patients in our general urology service and is deemed convenient, thorough and satisfactory by them It should be facilitated going forward in appropriately selected patients

Suprapubic catheter insertion and exchange is a common urological procedure, but it is not without risks and complications. While bowel perforation is a recognised complication at suprapubic catheter insertion, it is not commonly reported at suprapubic catheter exchange. We report our experience of recognition, diagnosis and subsequent successful management of the most important complication related to suprapubic catheters.

The interface between nanotechnology and biology needs to be well understood for improved outcome in medical applications. In other words, we need to know the interaction of nanoparticles (unit cells in nanotechnology) with cells (unit cells in biology) for improved outcome in diagnosis, imaging and therapeutic techniques. In this chapter, recent progress in the understanding of how size, shape and surface properties of nanoparticles (NPs) affect intracellular uptake, transport and processing of NPs will be discussed. Gold NPs are used as a model system in this regard as their size, shape and surface properties can be easily tailored. These findings provide useful information to tailor nanoparticle-based devices at the single cell level for effective applications in diagnosis, therapeutics and imaging.

The hydrolysis of isatoic anhydride 1, its 5-nitro 7; (X = NO2, R = H) and N-methyl derivatives in water at 25 °C occurs mainly via direct HO– attack on the neutral substrate. At high pH where 1 and 7(X = NO2, R = H) are ionized, the o-carboxyphenyl isocyanate 8b is formed in equilibrium with the anion 8a, and this undergoes a competing reaction with HO–(but at a slower rate). Reaction with amines at the anhydride carbonyl (C-4) which occurs at pH < 10 is characterized by a βnuc value of +1.0 but is highly sensitive to the steric bulk of the attacking amine. In consequence reaction at the isocyanate in the anion 8(X = H) is only important with bulky amines. With the 5-nitro derivative (pKa 6.7), reaction with the conjugate base can be measured even with non-hindered bases; these yield a βnuc value of 0.31, providing strong evidence that reaction occurs via the isocyanate 8b(X = NO2). The implications for heterocyclic synthesis starting from isatoic anhydride are considered.

The rate of hydrolysis of 1-phenylcarbamoylimidazole (3) in water at 30° is markedly depressed by the addition of imidazole in the pH region 6–10. This is rationalised in terms of the formation of a small equilibrium concentration of phenyl isocyanate in solution. Phenyl isocyanate, besides reacting with imidazole to regenerate (3), can also be competitively trapped by H2O, HO–, and other nucleophiles; the relative rates of reaction of HO– and H2O with phenyl isocyanate are 7 × 105: 1. Phenyl isocyanate also shows a low sensitivity to the nature of primary amine nucleophiles with a Bronsted β value of 0.30. Secondary and α-effect amines lie on the same correlation line as primary amines, consistent with a transition state in which there is little bond formation. In all cases, urea formation shows simple second-order kinetics (first order each in amine and phenyl isocyanate) and no catalyiss by general acids or bases (or by products formed) is obseved; this contrasts with the results of previous studies which have been carried out in non-aqueous solution.

The kinetics of hydrolysis of 1-(N1-aroylamidino)-3,5-dimethylpyrazoles (3) have been studied at high and in 24·5% methanol at 30°. At high pH (>11) a specific base catalysed elimination occurs with the formation N-cyanoarenecarboxamides (which, stabilized as the anions, do not undergo further reaction) and 3,5-dimethylpyrazole. Variation of the N-aroyl substituent (in 1·0M-HO– in water) gave ρ=+0·45. In neutral solution is unreactive but acid hydrolysis results in direct formation of aroylureas. This reaction is specifically acid catalysed and the apparent pKa required to fit the kinetic data [1·40 in 24·5% methanol for the unsubstituted conmpound (3; X = H)] is the same as the measured spectrophotometric pKa. Data for the variation of the N-aroyl substituent are also presented and are consistent with a mechanism involving water attack on protonated (3). Kinetic data are also presented for N-benzoyl-S-methylisothiourea which also shows a rapid base-catalysed elimination (reflecting the improved leaving group, MeS–, relative to pyrazole anion) to give N-cyanobenzamide.

N-Phenylcarbamoylimidazole (2) is converted into aniline and imidazole near neutral pH but is relatively unreactive in acidic and basic solution. The rate of hydrolysis of (2) varies in a complex way as the pH of the medium [H2O; 30°; µ= 1·0 (KCl)] is changed, reaching two maxima at pH ca. 4·5 and 10·0. It is proposed that the zwitterionic tautomer (4) of (2) is the reactive species over the entire pH range [except in highly basic solution where the conjugate base of (2) reacts]. The rate of decomposition of the zwitterion (to imidazole and phenyl isocyanate initially) is so rapid (t½ca. 10–4 s) that the diffusion-controlled proton transfers involved in the formation of the zwitterion become rate limiting in the pH region 4–10. Addition of sufficient concentration of general acids or bases (except imidazole) can cause a change in the rate-limiting step to zwitterion decomposition in this pH region. Data are also presented for 1-phenylcarbamoylbenzimidazole (14), 1-(p-bromophenylcarbamoyl)imidazole (11), and 3,5-dimethyl-1-phenylcarbamoylpyrazole (12) and are interpreted similarly. The catalysis of the diffusion-controlled proton transfer steps by primary, secondary, and tertiary amine catalysts is investigated in detail for the hydrolysis of (14). Addition of low concentrations (< 5 × 10–5M) of imidazole in neutral solution initially increases the rate of hydrolysis of (2)(imidazole acting as a general acid–base) but high concentrations of imidazole actually retard the overall rate of hydrolysis of (2). This is interpreted in terms of imidazole acting as an efficient trap for the phenyl isocyanate intermediate, thus regenerating the substrate.