. Author manuscript; available in PMC: 2013 Jul 29.

Published in final edited form as: Bioorg Med Chem Lett. 2010 Apr 24;20(12):3688–3691. doi: 10.1016/j.bmcl.2010.04.086

Table 1.

Relative affinities of amino acid and melphalan analogs for the system LAT1 transporter, expressed as the K_i for inhibition of the uptake of L-[¹⁴C]-leucine into rat brain via the blood–brain barrier.

Amino acid	Nitrogen mustard	K_i^a (μM ± S.E.M)
L-Phenylalanine	2	55 ± 4
(±)-2-Amino-1,2,3,4-tetrahydro-2-naphthoic acid		7.7 ± 0.8
	5a	8.5 ± 0.6
	5b	68 ± 9
	5c	0.079 ± 0.006
	5d	252 ± 44
(±)-2-Aminoindane-2 carboxylic acid		12.5 ± 1.1
	6	5.0 ± 0.6
(±)-2-Aminobenzo-bicyclo-[2.2.1]heptane-2′-exo-carboxylic acid		26 ± 1
	7	2.1 ± 0.2

n = 9–12.