Abstract: The present invention provides novel 1,3,5-triazinane-2,4,6-trione derivatives, such as compounds of any one of Formulae (I) and (II), and salts thereof, and methods of preparing the compounds. Also provided are compositions including a compound of the invention and an agent (e.g., an siRNA, mRNA, or plasmid DNA). The present invention also provides methods and kits using the compositions for delivering an agent to a subject (e.g., to the liver, spleen, or lung of the subject) or cell and for treating and/or preventing a range of diseases, such as genetic diseases, proliferative diseases, hematological diseases, neurological diseases, liver diseases, and lung diseases.

Abstract: ?-Aminoamidine polymers and methods of preparing a-aminoamidine polymers by reacting by reacting one or more amines with one or more isocyanides and one or more aldehydes are described. Methods of preparing a-aminoamidine polymers from commercially available starting materials are also provided, wherein the starting materials are racemic or stereochemically pure. a-Aminoamidine polymers or salt forms thereof are preferably biodegradable and biocompatible and may be used in a variety of drug delivery systems and for other purposes as well such as, for example, coatings, additives, excipients, plastics, and materials, etc. Given the amino moiety of these ?-aminoamidine polymers, they are particularly suited for the delivery of polynucleotides. Complexes, micelles, liposomes or particles containing the inventive ?-aminoamidine polymers and polynucleotides can be prepared. The inventive ?-aminoamidine polymers may also be used in preparing microparticles for drug delivery.

Abstract: Provided herein are lipidoids that may be prepared from the conjugate addition of alkylamines to acrylates. In some embodiments, provided lipidoids are biodegradable and may be used in a variety of drug delivery systems. Given the amino moiety of the lipidoids, they are well-suited for the delivery of polynucleotides, in addition to other agents. Nanoparticles containing the inventive lipidoids and polynucleotides have been prepared and have been shown to be effective in delivering siRNA.

Abstract: The invention features an improved lipid formulation comprising a cationic lipid of formula (A), a neutral lipid, a sterol and a PEG or PEG-modified lipid, where R1 and R2 are independently alkyl, alkenyl or alkynyl, each can be optionally substituted, and R3 and R4 are independently lower alkyl or R3 and R4 can be taken together to form an optionally substituted heterocyclic ring. In one embodiment, R1 and R2 are independently selected from oleoyl, pamitoyl, steroyl, linoleyl and R3 and R4 are methyl. Also disclosed are targeting lipids, and specific lipid formulations comprising such targeting lipids.