2,2:3,3-Bis(4'-hydroxymethylethylenedioxy)-1,7,7-trimethylbicyclo[2.2.1]heptane, abbreviated as CaG, is a compound obtained by transforming a ketone group to a ketal group with camphorquinone and glycerol. The CaG diol has a complex and rigid structure and two primary hydroxyl groups. A polyester series was synthesized with the CaG diol, ethylene glycol, and dimethyl terephthalate. The polyesters exhibited adequate thermal stability up to nearly 330 °C and had a high T, which steadily increased from 78 to 129 °C as the content of CaG increased. A high proportion of the CaG moiety led to an amorphous region that is susceptible to hydrolysis and promoted degradation of the polyester in acidic conditions. Depending on the proportion of CaG in the polymer, the hydrolytic degradation of the polyesters was adjustable.
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http://dx.doi.org/10.1021/acs.biomac.7b00761 | DOI Listing |
Biomacromolecules
August 2017
Department of Chemical Engineering, College of Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
2,2:3,3-Bis(4'-hydroxymethylethylenedioxy)-1,7,7-trimethylbicyclo[2.2.1]heptane, abbreviated as CaG, is a compound obtained by transforming a ketone group to a ketal group with camphorquinone and glycerol.
View Article and Find Full Text PDFProstate
May 2010
Fred Hutchinson Cancer Research Center, Cancer Prevention Program, Seattle, Washington 98109-1024, USA.
Background: To examine whether androgen receptor (AR) CAG repeat length was associated with the risk of incident benign prostatic hyperplasia (BPH).
Methods: A nested case-control study of 416 BPH cases and 527 controls drawn from Prostate Cancer Prevention Trial placebo-arm participants who were free of BPH at baseline. BPH was assessed over 7 years and was defined as receipt of medical or surgical treatment, two scores > 14 on the International Prostate Symptom Score (IPSS), or two increases in IPSS > or = 5 with at least one score > or = 12.
Chem Res Toxicol
November 1991
Department of Chemistry, University of Rochester, New York 14627-0216.
The relative reactivity of the chemical carcinogen (+/-)-7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene [(+/-)-anti-BPDE] to the guanine bases of the first two coding exons of the human c-Ha-ras1 protooncogene is determined to test if (+/-)-anti-BPDE reactivity is correlated with mutations reported for human c-Ha-ras1 protooncogene activation. Plasmid DNA containing the sequence for the human c-Ha-ras1 gene is modified with (+/-)-anti-BPDE to provide approximately 1 covalent adduct per 250 bp. High-resolution mapping of the covalent adducts is achieved by laser-induced photolysis of 32P-labeled restriction fragments of the BPDE-modified plasmid DNA.
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