This methodology opens the avenue to scalable synthesis of DNA-mimetic sequential polymers in a fast, concise, precise and reliable manner. The SCFPs with independently hetero-functional groups are tolerant to further selective modification. The whole process is catalyst-free and the monomers are commercially available. Here we present a facile and general strategy to synthesize SCFPs with tailored hetero-functional groups, such as OH/NH 2, OH/COOH and NH 2/N 3, via radical-initiated step-growth (RISG) polymerization in water. Moreover, other topological SCFPs such as sequential dendritic polymers have never been reported yet, although three-dimensional biomacromolecules widely exist in nature. Therefore, to readily and efficiently synthesize sequence-controlled functional polymers (SCFPs) is still a big challenge. However, all of the artificial SCPs have no independent functional groups suspended on backbone 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 and thus it is quite difficulty to further design and introduce specific functional moieties on those SCPs. 7, 3) step-by-step increment such as the famous Merrifield solid-phase synthesis 8 and a recently developed liquid-phase synthesis employing soluble polymer support and a special activation/addition process 9, 4) kinetic control in chain cross propagation (i.e., typical copolymerization of styrene and maleic anhydride) 10, 11, 5) polymerization of short sequence-defined oligomers to produce periodic copolymers 12 and 6) quantitative and regioselective insertion of monomer into polymer chains 13, 14. Accordingly, various strategies have been developed to synthesize SCPs since 1963 1, 2, 3, 4, 5 including, 1) the most extensively applied condensation polymerization between two bifunctional symmetric or nonsymmetric monomers 6, 2) templating polymerization aided by complementary macromolecule templates or joint monomers templates recently innovated by Sawamoto et al. To achieve such advanced functions, both the sequentially repeated units and the self-recognizing functional groups are the crucial prerequisites.
#Thiol functional group code
For instance, the genetic code is stored in the sequence of bases and instructs the processes of DNA replication, transcription and translation. SCPs are crucial in biological functions.
The results indicate that some aspects of the amide bond and proper distance between this amide and the thiol/thioester moiety are critical for activity of CoA ester-utilizing enzymes.Sequence-controlled polymers (SCPs) represent a kind of macromolecules composed of orderly arranged monomer units of different chemical nature 1. Analogues of several CoA thioesters in which the amide bond was replaced with a hemithioacetal linkage exhibited no measurable activity with the appropriate enzymes. An analogue in which an extra methylene group was inserted between the amide bond and the thiol group showed less than 4-fold diminished binding to the three enzymes but exhibited less than 1% activity relative to acetyl-CoA with carnitine acetyltransferase and no measurable activity with the other two enzymes. An analogue of acetyl-CoA in which this amide bond is replaced with an ester linkage was a good substrate for the enzymes carnitine acetyltransferase, chloramphenicol acetyltransferase, and citrate synthase, with K(m) values 2- to 8-fold higher than those of acetyl-CoA and V(max) values from 14 to >80% those of the natural substrate. Analogues of coenzyme A (CoA) and of CoA thioesters have been prepared in which the amide bond nearest the thiol group has been modified.
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