Figure 6.

The chemical structures of polymeric NSGMs. A) Polyacrylic acid polymers 13 were found to bind ATIII with K_D values of 1.0–2.3 µM at pH 6.0 and 34–180 µM at pH 7.4. The polymers accelerated ATIII-mediated FXa inhibition much better at pH 6.0 (15– 284-fold) than at pH 7.4 (6.2–17-fold). The polymers also accelerated ATIII-mediated thrombin inhibition in comparable fashion at the two pHs; pH 6.0 (24–1392-fold) and pH 7.4 (114–1109-fold). Polyacrylic acid polymers have opened up an opportunity to developing orally bioavailable, carboxylate-based ATIII activators. B) Chemo-enzymatically prepared oligomers of 4-hydroxycinnamic acids, known as dehydrogenation polymers (DHPs) displayed interesting anti-coagulant (thrombin inhibitors and ATIII activators), anti-fibrinolytic (plasmin inhibitors), and anti-emphysema (inhibitors of pulmonary elastolysis, oxidation, and inflammation) properties. The oligomers were prepared by peroxidase-catalyzed oxidative coupling of caffeic 14 (CDSO3), ferulic 15 (FDSO3), and sinapic 16 (SDSO3) acids, followed by sulfation using SO3–NEt3 complex. Various analytical studies suggested that the DHPs are heterogeneous and polydisperse preparations that are composed of inter-monomer linkages similar to those found in natural lignins including β−5, β-O-4, β-β and β−5. DHPs were later named as low molecular weight lignins (LMWLs).