Privileged substructures are of potentially great importance in medicinal chemistry. These scaffolds are characterized by their ability to promiscuously bind to a multitude of receptors through a variety of favorable characteristics. This may include presentation of their substituents in a spatially defined manner and perhaps also the ability to directly bind to the receptor itself, as well as exhibiting promising characteristics to aid bioavailability of the overall molecule. It is believed that some privileged substructures achieve this through the mimicry of common protein surface elements that are responsible for binding, such as β- and gamma;-turns. As a result, these structures represent a promising means by which new lead compounds may be identified.

The combinatorial synthesis of bicyclic privileged structures or privileged substructures

The biochemistry and medical significance of the flavonoids.

Recent Developments in Ring Opening Polymerization of Lactones for Biomedical Applications

Polycaprolactone (PCL) is an important polymer due to its mechanical properties, miscibility with a large range of other polymers and biodegradability. Two main pathways to produce polycaprolactone have been described in the literature: the polycondensation of a hydroxycarboxylic acid: 6-hydroxyhexanoic acid, and the ring-opening polymerisation (ROP) of a lactone: e-caprolactone (e-CL). This critical review summarises the different conditions which have been described to synthesise PCL, and gives a broad overview of the different catalytic systems that were used (enzymatic, organic and metal catalyst systems). A surprising variety of catalytic systems have been studied, touching on virtually every section of the periodic table. A detailed list of reaction conditions and catalysts/initiators is given and reaction mechanisms are presented where known. Emphasis is put on the ROP pathway due to its prevalence in the literature and the superior polymer that is obtained. In addition, ineffective systems that have been tried to catalyse the production of PCL are included in the electronic supplementary information for completeness (141 references).

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Synthesis of polycaprolactone: a review

Biodegradable synthetic polymers: Preparation, functionalization and biomedical application

Lipase-catalysed selective deacetylation of phenolic/enolic acetoxy groups in peracetylated benzyl phenyl ketones.

/pdf/mechanism-of-lactic-acid-formation-catalyzed-by-a-2et65hf2i9.pdf

Mechanism of lactic acid formation catalyzed by a macrocyclic chromium(III) complex. A comparison with the glyoxalase I enzyme

The Jak2 Inhibitor, G6, Alleviates Jak2-V617F-Mediated Myeloproliferative Neoplasia by Providing Significant Therapeutic Efficacy to the Bone Marrow

Highly crystalline directional polycaprolactones (PCLs) based on two tetrahydroxy methyl resorcin[4]arene initiators were synthesized by a “core first” method via ring-opening polymerization of e-caprolactone catalyzed by Sn(Oct)2 in bulk at 120 °C. The synthesized polymers were characterized by nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and wide angle X-ray scattering (WAXS). The structures of tetra-arm PCLs based on resorcinarenes were confirmed by 1H NMR analysis. The thermal properties were evaluated using DSC and TGA. The spatial directionality, a consequence of the rigid bowl shaped resorcinarene cavitand core, of the PCL chains influenced the thermal properties and crystallinity of the polymers. The melting temperature (Tm), decomposition temperature (Td) and % crystallinity (%Xc) of the directional PCL from the rigid core cavitand 2c were significantly higher than those of the linear counterpart and the PCL from the somewhat flexible cavitand core 3c. The data implies that the spatial directionality of the polymer chains in multi-arm polymers can be used to manipulate their thermal and physical properties. Detailed analysis of the two tetra-hydroxy resorcinarene initiators and a comparison with linear PCLs is discussed.

Influence of a resorcin[4]arene core structure on the spatial directionality of multi-arm poly(ε-caprolactone)s

An oligomer composed of a carbohydrate head group and an oligomer chain is disclosed. Methods for increasing the oligomerization rates of lactones and cyclic carbonates are also disclosed.

Kirpal S. Bisht

Papers

Lipase-catalysed selective deacetylation of phenolic/enolic acetoxy groups in peracetylated benzyl phenyl ketones.

Mechanism of lactic acid formation catalyzed by a macrocyclic chromium(III) complex. A comparison with the glyoxalase I enzyme

The Jak2 Inhibitor, G6, Alleviates Jak2-V617F-Mediated Myeloproliferative Neoplasia by Providing Significant Therapeutic Efficacy to the Bone Marrow

Influence of a resorcin[4]arene core structure on the spatial directionality of multi-arm poly(ε-caprolactone)s

Cyclic ester ring-opened oligomers and methods of preparation