A series of analogues of Pro-Leu-Gly-NH2 (PLG) in which the leucine residue has been replaced with the aliphatic amino acids L-isoleucine, L-2-aminohexanoic acid (Ahx), L-2-aminopentanoic acid, and L-2-aminobutanoic acid and the aromatic amino acids L-phenylalanine, L-phenylglycine, L- and D-2-amino-4-phenylbutanoic acid, L-O-methyltyrosine, and L-4-nitrophenylalanine have been synthesized. These analogues were tested for their ability to enhance the binding of the dopamine receptor agonist 2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (ADTN) to striatal dopamine receptors. Two of the above analogues, Pro-Ahx-Gly-NH2 (3) and Pro-Phe-Gly-NH2 (6), showed significant activity in this assay system. Pro-Ahx-Gly-NH2 produced a 16% enhancement of ADTN binding at 0.1 microM, while Pro-Phe-Gly-NH2 enhanced the binding of ADTN by 31% at a concentration of 1 microM.

α‐Phenyl‐4‐nitrobenzenemethanol (3) reacted with 1 M sodium hydroxide to yield 4, 4′‐dibenzoyl‐azoybenzene (5) (51%), 4‐hydroxy‐4′‐benzoylazobenzene (6) and benzoic acid (12% each), and smaller amounts of 4‐aminobenzophenone and 4‐nitrobenzophenone. Both α‐phenyl‐2‐nitrobenzenemethanol (9) and 3, 5‐dimethyl‐4‐nitrobenzenemethanol (10a) did not react with 1 M sodium hydroxide, presumably due to steric hindrance. α‐(p‐Nitrophenyl)‐4‐pyridinemethanol (14) and its N‐oxide 11 with 1 M sodium hydroxide yielded 4,4′‐diaroylazoxybenzenes 15a and 12a, respectively, 4,4′‐diaroylazobenzenes 15b and 12b, respectively, as well as 4‐hydroxy‐4′‐aroylazobenzenes 16 and 13, respectively. The relative reaction rates were 11 > 14 > 3. Studies with 11 showed that the nitro group is involved in the redox reaction in preference to the N‐oxide group.

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The lithium 1‐alkynyltrialkylborates (III), prepared from the trialkyl boranes (I) and the lithium acetylides (II), react with trimethylsilylmethyl triflate (IV) to give the allylsilanes (V).