Caged compounds development

Example 28 a caged compound includes a photocleavable-protecting group that masks an essential functionality upon removal by photolysis [58]. Imperiali and associates have developed an interassembly approach for the synthesis of peptides containing l-(2-nitrophenyl)ethyl-caged phos-phamino acids [59]. The peptides described in that paper are based on phosphorylation sites of kinases involved in cell movements. 

Loudwig, S., Specht, A. and Goeldner, M. (2002) Caged compounds, the photolabile precursors of bioactive molecules. Developments and prospects. Actualite Chimique, (1), 7-12. 

Cage compounds. Another important use of RSi(OMe)3 compounds is in the preparation of compounds with nice cage architecture as depicted in Figure 5 is well-known now, but it is still attractive since it offers access to well-defined building units for hybrid materials. The most recent developments in this field concent the preparation of silsesquioxanes with liquid crystal properties,45, silsesquioxanes as building blocks of a three-dimensional structure46-49 and silsesquioxanes that mimic zeolite structures with an incompletely condensed structure (open cage) or with incorporation of other metals. 

Desferrioxamine E and its analogues are siderophores widely produced by Streptomyces and related bacteria.81 Their major role is ferric transportation cells secrete these cage compounds to their environment and then uptake their ferric-bound form (ferrioxamines) by the activity of a specific transporter to utilize ferric. Probably, the organisms had developed this complex retrieval system due to the insolubility and low availability of ferric in the natural environment. 

The Bhcmoc group was developed as a photochemically removable protective group for caged compounds. Among the series tested this one showed the highest photochemical efficiency in its release of an alcohol. ... 

Higuchi H,Ueda I (1992) Recent Developments in the Chemistry of Cubane. In Osawa E, Yonemitsu O (eds) Carbocyclic Cage Compounds Chemistry and Applications. VCH Publishers, New York... 

A new gravimetric method is developed for iron(III) in which the iron is precipitated in crystalline form with an organoboron cage compound. The accuracy of the method is checked by analyzing the iron in an ore sample and comparing with the results using the standard precipitation with ammonia and weighing of Fe Oa. The results, reported as % Fe for each analysis, were as follows ... 

Cage compounds have always been a subject of interest and fascination for chemists [2, 3]. The main reasons for this are probably the symmetry characteristics of esthetic molecules such as cubane (1) [4], prismane (2) [5], or pentaprismane (3) [6] (Scheme 6-1). In addition, the unusual reactivities of these polycyclic carbon systems have helped to promote the interest and actuality of such compounds over several decades. Finally, these unusual systems have often caused chemists to reconsider the conventional concepts of bonding in regard to atomic separations and bond angles and to develop new theories. 

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