Hollow Sphere Formation from a Three-Dimensional Structure Composed of an Adamantane-Based Cage

Nascent pharmacological advancement in adamantane derivatives

The adamantane moiety has attracted significant attention since its discovery in 1933 due to its remarkable structural, chemical, and medicinal properties. This molecule has a notable impact in the therapeutic field because of its "add-on" lipophilicity to any pharmacophoric moieties. As in the case of molecular hybridization, in which one pharmacophore is attached to another one(s) with a probability of increasing the biological activity, adding an adamantane unit improves the absorption distribution, metabolism and excretion properties of the resultant hybrid molecule. This review summarizes various reports highlighting the biological activities of adamantane-based synthetic compounds and their structure-activity relationship study. The information presented in this review may open up possible dimensions for adamantane-based drug development and discovery in the pharmaceutical industry after proper structural modifications.

Post‐Synthetic Modification of a Porous Hydrocarbon Cage to Give a Discrete Co 24 Organometallic Complex**

A new alkyne‐based hydrocarbon cage was synthesized in high overall yield using alkyne‐alkyne coupling in the cage forming step. The cage is porous and displays a moderately high BET surface area (546 m² g⁻¹). The cage loses crystallinity on activation and thus is porous in its amorphous form, while very similar cages have been either non‐porous, or retained crystallinity on activation. Reaction of the cage with Co₂(CO)₈ results in exhaustive metalation of its 12 alkyne groups to give the Co₂₄(CO)₇₂ adduct of the cage in good yield.

Synthesis of Enantiopure Hydrocarbon Cages Based on an Optically Resolved C3-Symmetric Triaminotribenzotriquinacene

The synthesis of the enantiomerically pure, D₃-symmetric covalent hydrocarbon cages (+)-(M,M)-4 and (-)-(P,P)-4 bearing two C₃-symmetrically functionalized tribenzobenzotriquinacene (TBTQ) vertices is reported. The enantiomerically pure TBTQ building blocks (+)-(M)-5 and (-)-(P)-5 were prepared via the diastereomeric TBTQ triamides obtained by use of both Boc-d- and Boc-l-phenylglycine as chiral auxiliaries.

Cylindrical macrocyclic compounds synthesized by connecting two bowl-shaped calix[3]aramide moieties: structures and chiroptical properties

Calix[3]aramide-based macrocycles 1 were successfully synthesized by a Glaser coupling reaction of two meta-calix[3]aramide moieties that have three ethynyl groups. The obtained macrocycles have stereoisomers: an enantiomeric pair and a meso form based on a combination of amide bond directions in the calix[3]aramide moieties at both ends of the molecule. Characteristic absorption spectra derived from the 1,4-diphenylbutadiyne structure were observed, while their ECD spectra were mirror-images. Single-crystal X-ray analysis revealed that each stereoisomer had a cylindrical rigid shape, and the absolute structure of the chiral-form was also assigned by comparing the Flack parameters. Mirror-image VCD spectra were observed for the enantiomeric chiral forms, and a VCD signal pattern of one enantiomer corresponded to that predicted by the relationship between the dihedral angle of the pair of C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> O groups.

Chiral macrocyclic compounds whose absolute configurations were derived from the amide bond direction were synthesized by homo coupling of meta-calix[3]aramide derivatives.

Synthetic Advances in the C–H Activation of Rigid Scaffold Molecules

The remarkable structural and electronic properties of rigid non-conjugated hydrocarbons afford attractive opportunities to design molecular building blocks for both medicinal and material applications. The bridgehead positions provide the possibility to append diverse functional groups at specific angles and in specific orientations. The current review summarizes the synthetic development in CH functionalization of three rigid scaffolds namely: (a) cubane, (b) bicyclo[1.1.1]pentane (BCP), (c) adamantane.

1 Introduction

2 Cubane

2.1 Cubane Synthesis

2.2 Cubane Functionalization

3 Bicyclo[1.1.1]pentane (BCP)

3.1 BCP Synthesis

3.2 BCP Functionalization

4 Adamantane

4.1 Adamantane Synthesis

4.2 Adamantane Functionalization

5 Conclusions and Outlook

Gelation of Luminescent Supramolecular Cages and Transformation to Crystals with Trace-Doped-Enhancement Luminescence

Supramolecular gels with hierarchical order and complexity have been assembled. The gels contain well-defined Ag₄L₂ luminescent supramolecular cages as cores, which are cross-linked via Ag-P coordination bonding. The resulting gels are highly luminescent and exhibit rich stimuli-responsive behaviors toward mechanical and chemical (nitroexplosive and anions) stimuli. The gels could be transformed to highly luminescent crystal materials upon addition of halogen anions, in which only traces of lumiphor are accommodated in a host crystal matrix.