本发明公开了一种生物降解高分子材料的内酯单体，其以环己酮为起始原料，首先与丙烯酸苄酯加成得a-（丙酸苄酯基）环己酮，然后经氧化制得；或以a-取代环己酮为起始原料，先与苯甲醇进行酯交换反应，然后经氧化制得。本发明设计并合成的己内酯单体的最大优点在于，具侧链酯在水解时内酯键不受影响。此外，本发明还具有合成条件温和、安全；所用原料简单、廉价、丰富、易得等优点。

Polycaprolactone/poly (ethylene oxide)/polylactide tri-component copolymers (PCEL) with different compositions were synthesized by copolymerization of ε-caprolactone and L-lactide in the presence of poly (ethylene glycol) using stannous octoate as a catalyst. The copolymers were pnrified and characterized by various analytical techniques such as GPC, FT-IR, I H NMR, 13C NMR, DSC, and X-ray diffraetometry. It was evidenced that these eopolymers were pure tri-componcnt compounds which exhibited partially random chain structures, and possessed good mechanical properties and variable biodegradability.

Carbamazepine has been found to crystallize as a new polymorph that is stable at room temperature. We report the crystal structure of this C-centered monoclinic form (space group C2/c, cell parameters: a=26.609, b=6.9269, c=13.957, b=109.702), which consists of hydrogen bonded dimers with an anti-disposition. This represents the third modification of carbamazepine that has been crystallographically characterized, and the fourth for which cell parameters have been determined. Thus, it is designated as form IV of carbamazepine. Differences between the packing of the various polymorphs are discussed.

Hydroxyl-functionalized three-arm poly(∈-caprolactone)s (PGCL-OHs) were synthesized by the ring-opening polymerization of ∈-caprolactone in the presence of glycerol (as the core) and stannous octoate. The effect of the feed ratio of ∈-caprolactone to glycerol on the ring-opening polymerization was studied. These three-arm PGCL-OHs were then converted into double-bond-functionalized three-arm poly(∈-caprolactone)s (PGCL-Mas) by the reaction of PGCL-OH with maleic anhydride in the melt at 130℃. The quantitative conversion of hydroxyl functionality was achieved ata low mo lecular weight. The resulting PGCL-OH and PGCL-Ma were characterized with gel permeation chromatography, Fourier transforminfrared, 1H NMR, 13C NMR, and differential scanning calorimetry.

Biocompatible biodegradable polymer or copolymer is capped at one end has free hydroxyl at the other end. The free hydroxyl can be reacted to link a plurality of functional groups some or each of which can be reacted to attach directly or via a spacer molecule a moiety contaning an aminoxyl-contaning radical or to a moiety comprising other drug molecule residue or a moiety comprising other biologically active agent residue.