Hayes and Hunter

Scheme 3.24 Cyclisation step of the Hayes and Hunter synthesis of p-methylcalix[4]arene.

Noting Zinke s claim to have isolated cyclic tetramers from the condensation of p-substituted phenols and formaldehyde, Hayes and Hunter in 1956 sought to... 

Scheme i. 10-Step synthesis of />-methylcalix[4)arene (Hayes and Hunter method). 

The Hayes and Hunter stepwise synthesis has certain drawbacks it is long and... 

Fig. 10. Calixarenes synthesized by Kammerer et al. via the Hayes and Hunter stepwise method...

Scheme 2. Stepwise synthesis of p-phenylcalix[4]arene by the Hayes and Hunter method.

Recognizing the deficiencies in the Hayes and Hunter synthesis, Bohmer, Chhim, and Kammerer 96) have explored a more convergent approach which retains much of the flexibility of the sequential approach. It involves the condensation of a linear trimer (29) with a 2,6-iwhalomethylphenol (30), as illustrated in Scheme 3. Although short, this method suffers from quite low yields in the cyclization step, ranging from... 

Many years before Gutsche found effective synthetic procedures for the various calixarenes, Hayes and Hunter [14] reported a stepwise preparation of calixarenes. This method was many years later investigated in Mainz by Herman Kammerer and by Volker Bohmer [15]. Their method comprises the tedious synthesis of linear precursors and their subsequent cyclisation. 

Hayes BT, Hunter RF (1958) Phenol formaldehyde and allied resins VI rational synthesis of a cyclic tetranuclear/t-cresol novolak. J Appl Chem 8 743-748. 

Phenol-formaldehyde and allied resins VI Rational synthesis of a cyclic tetranuclear p-cresol novolak, B. T. Hayes and R. F. Hunter, J. Appl. Chem., 1958, 8, 743. 

Peng CC, Glassman PA, Trilli LE, Hayes-Hunter J, Good CB. Incidence and severity of potential drug-dietary supplement interactions in primary care patients an exploratory study of 2 outpatient practices. Arch Intern Med 2004 164(6) 630-636. 

B20. Beckett, G. J., Hunter, J. E., and Hayes, J. D., Hepatic damage in the rat following administration of thyroxine or triiodothyronine, assessed by measurement of plasma glutathione S-transferase YaYa concentrations. Clin. Chim. Acta 161, 69-79 (1986). 

This enzyme has been measured in a number of toxicology studies with hepatotoxins (Di Simplicio 1982 Beckett, Hunter, and Hayes 1986 Clarke et al. 1997 Kilty et al. 1998 van der Aar et al. 1998 Eaton and Bammier 1999 Coluccio et al. 2000 Giffen et al. 2002 Strelic et al. 2003 Awasthi 2006). However, it has yet to establish a place among the common enzyme measurements, possibly because of the short half-life (<90 minutes). Currently, alpha-GST may be measured by radioimmunoassay or enzyme immunoassays given the complexity of the GST enzyme family, it may be more successful if new assays can be developed (see Chapter 2). 

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