42417-76-5Relevant academic research and scientific papers
Environmentally Benign CO2-Based Copolymers: Degradable Polycarbonates Derived from Dihydroxybutyric Acid and Their Platinum-Polymer Conjugates
Tsai, Fu-Te,Wang, Yanyan,Darensbourg, Donald J.
, p. 4626 - 4633 (2016/05/19)
(S)-3,4-Dihydroxybutyric acid ((S)-3,4-DHBA), an endogenous straight chain fatty acid, is a normal human urinary metabolite and can be obtained as a valuable chiral biomass for synthesizing statin-class drugs. Hence, its epoxide derivatives should serve as promising monomers for producing biocompatible polymers via alternating copolymerization with carbon dioxide. In this report, we demonstrate the production of poly(tert-butyl 3,4-dihydroxybutanoate carbonate) from racemic-tert-butyl 3,4-epoxybutanoate (rac-tBu 3,4-EB) and CO2 using bifunctional cobalt(III) salen catalysts. The copolymer exhibited greater than 99% carbonate linkages, 100% head-to-tail regioselectivity, and a glass-transition temperature (Tg) of 37 °C. By way of comparison, the similarly derived polycarbonate from the sterically less congested monomer, methyl 3,4-epoxybutanoate, displayed 91.8% head-to-tail content and a lower Tg of 18 °C. The tert-butyl protecting group of the pendant carboxylate group was removed using trifluoroacetic acid to afford poly(3,4-dihydroxybutyric acid carbonate). Depolymerization of poly(tert-butyl 3,4-dihydroxybutanoate carbonate) in the presence of strong base results in a stepwise unzipping of the polymer chain to yield the corresponding cyclic carbonate. Furthermore, the full degradation of the acetyl-capped poly(potassium 3,4-dihydroxybutyrate carbonate) resulted in formation of the biomasses, β-hydroxy-γ-butyrolacetone and 3,4-dihydroxybutyrate, in water (pH = 8) at 37 °C. In addition, water-soluble platinum-polymer conjugates were synthesized with platinum loading of 21.3-29.5%, suggesting poly(3,4-dihydroxybutyric acid carbonate) and related derivatives may serve as platinum drug delivery carriers.
Synthesis of models of the BC ring systems of MPC1001 and MPC1001F
Dong, Shuai,Indukuri, Kiran,Clive, Derrick L. J.,Gao, Jin-Ming
, p. 8271 - 8274 (2016/07/06)
Piperazinedione 13, representing the BC rings of the anti-prostate cancer fungal metabolite MPC1001, was prepared by a route in which a sulfur-stabilized carbanion derived from 22 cyclizes onto the terminal ester of the pendant chain attached to N1. Another model, 14, was synthesized by cyclization of an α-ketoamide nitrogen onto an ester; 14 represents the BC rings of MPC1001F.
Synthesis and anticancer properties of RGD peptides conjugated to nitric oxide releasing functional groups and abiraterone
Nortcliffe, Andrew,Fleming, Ian N.,Botting, Nigel P.,O'Hagan, David
supporting information, p. 8343 - 8347 (2015/03/05)
A series of analogues of the integrin binding aspartic acid-glycine-arginine (RGD) peptide sequence were synthesised conjugated to nitric oxide (NO) donating functional groups. Also the cytotoxicity of abiraterone, a prostate cancer drug, was explored when it was conjugated in three part constructs to RGD sequences and NO releasing heterocycles. In general the analogues showed integrin binding affinity comparable to RGD reference compounds, and all released NO by the Griess test assay. Two analogues exhibited significant cytotoxic effects against PC3 and MCF7 cell lines.
Preparation of protected amino acids
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Page 3, (2008/06/13)
The present invention involves a process for preparing protected amino acids. The process produces a di-tert-butyl amino ester or an N-protected di-tert-butyl amino ester by transesterification of an acidic amino acid or an N-protected acidic amino acid. By-products of the transesterification reaction may be recycled for use as part of the starting material. The N-protected di-tert-butyl amino ester may be hydrogenated to form a di-tert-butyl amino ester, which may subsequently form a di-tert-butyl ester hydrocholride salt.
