The approach used satisfies fundamental structural requirements of the CODHs-active site modeling, as the incorporation of a Ni atom at the apex of an iron-sulfur cubane
's unique geometry imposes an angle of 90[degrees] on the C-C-C instead of the 109.5[degrees] normally found in [sp.sup.3] bonding, resulting in enormous strain energy.
In the early 1980s, Army researchers recognized that cubane derivatives, especially octanitrocubane, could pack an incredible punch.
Adding the eight nitro groups to cubane proved to be a challenge.
Cellular regulation of the iron responsive element binding protein: disassembly of the cubane
iron-sulfur cluster results in high affinity RNA binding.
The molecule cubane consists of just eight carbon atoms bonded together in--as its name indicates--the shape of a cube, with hydrogen atoms at the corners.
Now, researchers at the National Institute of Standards and Technology (NIST) in Gaithersburg, Md., and the University of Chicago have determined the structure of solid cubane at high temperatures.
Cubane's strained 90 [degrees] bonds store a lot of energy, so military scientists have tapped it as a potential high-powered explosive.
Solid cubane's structure at high temperatures remained elusive for so long because the compound sublimes readily: Crystals evaporate in minutes if left out on a table.
Lipscomb also knew of smaller boron compounds that resembled other carbon molecules: For example, the eight-carbon cubane
matches with a six-boron hydride ion.