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Solid-phase organic synthesis (SPOS) routes to target unsymmetrical polyamines and their acridinyl and dansyl conjugates have been developed based upon borane–pyridine complex (BAP) mediated reductive alkylation, azide reduction with triphenylphosphine, and the use of pent-4-enoyl (Pnt) as an orthogonal amine protecting group.

Novel cholesterol-polyamine carbamates have been prepared and their pKas determined potentiometrically for conjugates substituted with up to five amino functional groups and the binding affinity for calf thymus DNA has also been determined; these polyamine carbamates are models for lipoplex formation with respect to gene delivery (lipofection), a key first step in gene therapy.

N 1 -(Acridin-9-ylcarbonyl)spermine binds at 5′-pu-p-pu..5′-py-p-py sites of DNA with the acridine moiety asymmetrically intercalated, stacked between the two purine bases; the spermine moiety interacts with the homopyrimidine phosphodiester backbone of the intercalation site and protects against DNase I cleavage of this backbone, but does not protect against cleavage of the homopurine backbone at the same intercalation site.

Polyamine amides have been prepared from cholic and lithocholic acid by acylation of tri-Boc protected spermine and thermine and their binding affinities for calf thymus DNA were determined using an ethidium bromide fluorescence quenching assay; these polyamine amides are models for lipoplex formation with respect to gene delivery (lipofection), a key first step in gene therapy.

Novel 23-, 24- and 28-membered cyclic polyamine amides (cinnamamides) have been prepared by closure of diphenyl ethers; functionalized conjugates of spermidine and spermine underwent intramolecular aromatic nucleophilic substitution to afford nitro-substituted analogues of cadabicine class (24-membered polyamine lactam) alkaloids.

Electrorheological fluids have been prepared at low applied electric fields from BP oils containing microcrystalline cellulose (MCC); even at a low applied electric field of 500 V mm–1, 10% MCC in oils rich in linoleic or oleic acids behave as electrorheological fluids with the latter displaying significantly higher yield stresses.