Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built ...Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built on the 1,3,5-benzenetricarboxaldehyde core and endowed with a periphery of pentaerythritol groups has been developed.1,3,5-Tri(2,6-dioxa-4,4-dihydroxymethyl cyclohexyl) benzene(1) was synthesized by the condensation of 1,3,5-benzenetricarboxaldehyde with pentaerythritol in the presence of hot CHCl3 and p-methyl benzene sulfonic acid with 55% yield.By turning 1,3,5-benzenetricarboxaldehyde into its trioxime,it was protected to decrease the cross-linked reaction with compound 1 both including many groups.The reaction of compound 1 with 1,3,5-benzenetricarboxaldehyde trioxime and pentaerythritol afforded 1,3,5-tri{3-[2,4,8,10 -tetra-oxa-9(3,5-di(2,6-dioxa-4,4-dihydroxymethylcyclohexyl) phenyl]spiro\undecyl}benzene(2) by using I2 as the catalyst,and the yield was 25.2%.Product 2 and its intermediates were identified by IR,1H NMR,MS spectra and elemental analysis.展开更多
The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome ...The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome C in some extent.For example,the reduction rate of Fe Ⅲ cytochrome C to Fe Ⅱ cytochrome C by ascorbic acid was clearly slowed down because of the interaction between cytochrome C and PAMAM dendrimers.The reaction happened only betweem Fe Ⅲ cytochrome C and ascorbic acid,it showed a pseudo first order constant of 3 48 min -1 .When PAMAMC (G2 5 or 3 5) dendrimers were added in the reaction system,the pseudo first order constant dropped to 1 40 or 1 32 ?min -1 .The association constant of 1:1 cytochrome C G2 5C is 2 4×10 4 and the association constant of 1:1 cytochrome C G3.5C is 2 6×10 4.展开更多
文摘Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built on the 1,3,5-benzenetricarboxaldehyde core and endowed with a periphery of pentaerythritol groups has been developed.1,3,5-Tri(2,6-dioxa-4,4-dihydroxymethyl cyclohexyl) benzene(1) was synthesized by the condensation of 1,3,5-benzenetricarboxaldehyde with pentaerythritol in the presence of hot CHCl3 and p-methyl benzene sulfonic acid with 55% yield.By turning 1,3,5-benzenetricarboxaldehyde into its trioxime,it was protected to decrease the cross-linked reaction with compound 1 both including many groups.The reaction of compound 1 with 1,3,5-benzenetricarboxaldehyde trioxime and pentaerythritol afforded 1,3,5-tri{3-[2,4,8,10 -tetra-oxa-9(3,5-di(2,6-dioxa-4,4-dihydroxymethylcyclohexyl) phenyl]spiro\undecyl}benzene(2) by using I2 as the catalyst,and the yield was 25.2%.Product 2 and its intermediates were identified by IR,1H NMR,MS spectra and elemental analysis.
文摘The methyl ester terminated G1 5,2 5 and 3 5 poly(amidoamine) dendrimers (PAMAM) are hydrolyzed by using NaOH to obtain external carboxylate groups with them (PAMAMC).These dendrimers show interaction with cytochrome C in some extent.For example,the reduction rate of Fe Ⅲ cytochrome C to Fe Ⅱ cytochrome C by ascorbic acid was clearly slowed down because of the interaction between cytochrome C and PAMAM dendrimers.The reaction happened only betweem Fe Ⅲ cytochrome C and ascorbic acid,it showed a pseudo first order constant of 3 48 min -1 .When PAMAMC (G2 5 or 3 5) dendrimers were added in the reaction system,the pseudo first order constant dropped to 1 40 or 1 32 ?min -1 .The association constant of 1:1 cytochrome C G2 5C is 2 4×10 4 and the association constant of 1:1 cytochrome C G3.5C is 2 6×10 4.