Microwave-assisted synthesis of meso-carboxyalkyl-BODIPYs and an application to fluorescence imaging.

In this study, a significantly improved method for the synthesis of modular meso-BODIPY (boron dipyrromethene) derivatives possessing a free carboxylic acid group (which was subsequently coupled to peptides), is disclosed. This method provides a vastly efficient synthetic route with a > threefold higher overall yield than other reports. The resultant meso-BODIPY acid allowed for further easy incorporation into peptides. The meso-BODIPY peptides showed absorption maxima from 495-498 nm and emission maxima from 504-506 nm, molar absorptivity coefficients from 33 383-80 434 M-1 cm-1 and fluorescent quantum yields from 0.508-0.849. The meso-BODIPY-c(RGDyK) peptide was evaluated for plasma stability and (proved to be durable even up to 4 h) was then assessed for its fluorescence imaging applicability in vivo and ex vivo. The optical imaging in vivo was limited due to autofluorescence, however, the ex vivo tissue analysis displayed BODIPY-c(RGDyK) internalization and cancer detection thereby making it a novel tumor-integrin associated fluorescent probe while displaying the lack of interference the dye has on the properties of this ligand to bind the receptor.

(S)-Benzyl 3-phenyl-carbamoyl-1,2,3,4-tetra-hydro-isoquinoline-2-carboxyl-ate.

There are two independent mol-ecules in the asymmetric unit of the title compound, C(24)H(22)N(2)O(3). The heterocyclic ring assumes a twisted boat conformation and N-H⋯O inter-actions help to construct the three-dimensional network within the crystal packing.

(S)-Methyl 2-benzamido-3-(3,4-dimeth-oxy-phen-yl)propano-ate.

The dimethoxypbenzene ring in the title compound, C(19)H(21)NO(5), is gauche to the amide group and anti to the ester group. The chirality was confirmed to be S from two-dimensional NMR spectroscopy. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds and several short-contact inter-actions (2.07-3.45 Å) create chains parallel to [110]. The phenyl ring is disordered over two orientations in a 0.54 (2):0.46 (2) ratio.

(S)-Methyl 3-(3,4-dimeth-oxy-phen-yl)-2-[2-(diphenyl-phosphan-yl)benzamido]-propano-ate.

Mol-ecules of the title compound, C(31)H(30)NO(5)P, show a sttagered conformation about the C-C bond joining the dimeth-oxy-benzene group to the chiral centre, with the dimeth-oxy-benzene ring gauche to the amide group and anti to the ester group. In the crystal, weak inter-molecular N-H⋯O and C-H⋯O hydrogen bonds form layers parallel to (110).

(1R,3S)-N-Benzhydryl-2-benzyl-6,7-dimeth-oxy-1-phenyl-1,2,3,4-tetra-hydro-isoquinoline-3-carbothio-amide.

The title compound, C(38)H(36)N(2)O(2)S, has a heterocyclic ring that assumes a half-chair conformation. The phenyl rings of neighbouring mol-ecules align forming alternating chains parallel to [100] within the crystal packing. The absolute stereochemistry of the crystal was confirmed to be R,S at the 1- and 3-positions, respectively, by proton NMR spectroscopy. A single intra-molecular N-H⋯N hydrogen bond is observed.

Pore formation in phospholipid bilayers by amphiphilic cavitands.

Five new cavitands were prepared that have four pendant n-undecyl chains and "headgroups" connected by 2-carbon spacers. The headgroups were ~OCH(2)CONH-Ala-OCH(3), 1; ~OCH(2)CONH-Phe-OCH(3), 2; ~OCH(2)CONH-Ala-OH, 3; ~OCH(2)CONH-Phe-OH, 4; and ~OCH(2)CONHCH(2)CH(2)-thyminyl, 5. Pore formation by each cavitand was studied by use of the planar bilayer conductance experiment. All five compounds were found to form pores in asolectin bialyer membranes. Compounds 1-3 behaved in a generally similar fashion and exhibited open-close dynamics. Compounds 4 and 5 formed pores more rapidly, were more dynamic, and led more quickly to membrane rupture. Differences in the ion transport activity are rationalized in terms of structure and aggregate cavitand assemblies.