Biomedical subjects
Publications and source records attributed to David N Harpp.
The reaction of a series of 1,2-diols with S(2)Cl(2), 1,1'-thiobisbenzimidazole (4a), and 1,1'-dithiobisbenzimidazole (4b) provides the corresponding thionosulfites, ROS(S)OR (2), in moderate to good yield.
The reaction of aromatic thiols with sulfur dichloride and sulfur monochloride to form the corresponding aromatic trisulfides, 2a-d, and tetrasulfides, 3a-d, has been optimized with respect to yield and purity. The use of pyridine as an amine base and the use of freshly distilled sulfur monochloride (S(2)Cl(2)) serve as important alterations to the synthetic method. Their physical properties have been characterized, revealing some discrepancies with the literature.
Cp(2)MoS(2), 3, reacts with SO(2) in CH(2)Cl(2)/EtOH mixtures to give Cp(2)MoS(3)O(2), 4, wherein the SO(2) has inserted into the S-S bond to give a dithiosulfate ligand. Crystal data for 4: P2(1)/n, a = 7.6782(6) A, b = 14.580(3) A, c = 10.2730(10) A, beta = 92.04(1) degrees, V = 1149(3) A(3), Z = 4. Cp(2)MoS(2)O, 5, reacts with SO(2) in CH(2)Cl(2) to give low yields of 4 plus other identified products. 5 reacts with SO(2) in MeOH and EtOH to give the corresponding bis(O-alkylthiosulfate), 6a and 6b, respectively. Crystal data for 6a: P 1 macro, a = 8.3226(13) A, b = 8.4736(11) A, c = 12.382(2) A, alpha = 87.803(11) degrees, beta = 77.758(11) degrees, gamma = 86.383(12) degrees, V = 851.4(2) A(3), Z = 2.
Dicubyl disulfide (1) has been prepared in six steps from commercially available dimethyl-1,4-cubanedicarboxylate in 47% overall yield. In the final step, the previously unknown cubanethiol 2 was oxidized to disulfide 1. X-ray crystallography for 1 reveals the shortest tetragonal C-S bond on record (1.771 A). In contrast to previous generalizations, density functional theory calculations predict a low S-S rotation barrier similar to that for t-BuSSBu-t. Low-temperature (13)C NMR (600 MHz) confirms the prediction.