Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Chiral Memory in Dynamic Transformation from Porous Organic Cages to Covalent Organic Frameworks for Enantiorecognition Analysis

The preservation of chirality during a transformation process, known as the “chiral memory” effect, has garnered significant attention across multiple research disciplines. Here, we first report the retention of the original chiral structure during dynamic covalent chemistry (DCC)-induced structural transformation from porous organic cages into covalent organic frameworks (COFs). A total of six two-dimensional chiral COFs constructed by entirely achiral building blocks were obtained through the DCC-induced substitution of chiral linkers in a homochiral cage (CC3-R or -S) using achiral amine monomers. Homochirality of these COFs resulted from the construction of 3-fold-symmetric benzene-1,3,5-methanimine cores with a propeller-like configuration of one single-handedness throughout the cage-to-COF transformation. The obtained chiral COFs can be further utilized as fluorescence sensors or chiral stationary phases for gas chromatography with high enantioselectivity. The present study thus highlighted the great potential to expand the scope of functional chiral materials via DCC-induced crystal-to-crystal transformation with the chiral memory effect

Amphetamine-induced rotational behavior and HPLC analysis of striatal DA. A.

<p>Mean number of ipsilateral and contralateral turns made by each group over the 30-minute test period following an IP injection of 2 mg/kg amphetamine. The data for average number of ipsilateral and contralateral turns made per group were compared using a 2-tailed t-test (mCherry/saline n = 12, mCherry/MPTP n = 9, Pgc-1α/saline n = 12, Pgc-1α/MPTP n = 10). All relevant statistically significant comparisons are indicated on the graph. <b>B.</b> Box and whiskers plot of net ipsilateral turns per minute per group averaged across each group. Data were analyzed by one-way ANOVA, all relevant statistically significant comparisons are shown on the graph. <b>C.</b> Mean levels of striatal DA per mg of protein in the ipsilateral and contralateral (cntrl) striatum of each treatment group. Data were analyzed by paired t-test. (mCherry/saline n = 14, mCherry/MPTP n = 15, Pgc-1α/saline n = 15, Pgc-1α/MPTP n = 16) <b>D.</b> DA turnover in each treatment group. Data were analyzed by paired t-test for within group comparisons and Student’s t-test for between group comparisons.</p

Western blot data for the mitochondrial marker CoxIV.

<p>5 µg of whole-cell lysate from SN or striatal samples from saline or MPTP-treated Pgc-1α-microinjected mice was run on a 4–20% gradient gel and probed with anti-CoxIV and anti-b-actin antibodies. Each pair of lanes represents the contralateral (L) and ipsilateral (microinjected, R) SN respectively. Band densitometry data were analyzed using a paired Student’s <i>t</i>-test (n = 6 per group).</p

Th and Dat immunohistochemical staining and stereological cell counts. A.

<p>Representative images of the striatum used for Th densitometry with line graphs showing the integrated density of Th immunoreactivity for each animal analyzed. In the line graphs, for each animal a line connects the results for the uninjected side (contralateral, cntrl) and the microinjected side (mCherry or PGC-1a) (mCherry/saline n = 9, mCherry/MPTP n = 8, Pgc-1α/saline n = 9, Pgc-1α/MPTP n = 8). <b>B.</b> Representative images of the striatum used for Dat densitometry with line graphs showing the integrated density of Dat immunoreactivity for each animal analyzed (mCherry/saline n = 8, mCherry/MPTP n = 10, Pgc-1α/saline n = 11, Pgc-1α/MPTP n = 10). <b>C.</b> Representative images of the SN used for Th+ cell stereological analysis with line graphs showing the number of Th+ cells for each animal analyzed (mCherry/saline n = 10, mCherry/MPTP n = 8, Pgc-1α/saline n = 11, Pgc-1α/MPTP n = 10). <b>D.</b> Striatal Th immunoreactivity data for all treatment groups. Ipsilateral and contralateral striatal Th immunoreactivity within each treatment group was analyzed using a paired Student’s <i>t</i>-test (mCherry/saline n = 9, mCherry/MPTP n = 8, Pgc-1α/saline n = 9, Pgc-1α/MPTP n = 8). All significant comparisons are indicated on the graph. <b>E.</b> SN Th+ stereological cell count data for all treatment groups. The number of Th+ cells in the ipsilateral vs contralateral SNs within each treatment group were analyzed using a paired t-test. (mCherry/saline n = 10, Pgc-1α/saline n = 11). All significant comparisons are indicated on the graph. <b>F.</b> SN stereology data from MPTP-treated animals (mCherry and Pgc-1α) showing the number of Th+ neurons, Th- neurons (thionin staining) and total SN neurons (combined data). Data were analyzed using paired t-tests to compare the contralateral and ipsilateral (microinjected) SNs in each treatment group and Student’s t-test for comparing between groups. (mCherry/MPTP n = 8, Pgc-1α/MPTP n = 10). <b>G.</b> Western blot analysis of Th immunoreactivity in gross-dissected whole cell lysate SN and striatal samples (saline groups only). Band densitometry data was analyzed using a paired t-test to compare Th-band intensity between the contralateral and ipsilateral (microinjected) SN and striatum (n = 6 per group).</p