The unusual ring scission of a quinoxaline-pyran-fused dithiolene system related to molybdopterin.
نویسندگان
چکیده
The reduction of the dithiolene ligand, qpdt2-, a mimic of the biological molybdopterin cofactor, and the corresponding (η5-cyclopentadienyl)cobalt(iii) complex [(qpdt)CoIIICp] was studied. It was found that in both cases an unprecedented ring scission reaction took place in acidic medium. All new reaction products have been spectroscopically and structurally characterized. Plausible mechanisms for the formation of these products were also proposed.
منابع مشابه
Solvent-Dependent Pyranopterin Cyclization in Molybdenum Cofactor Model Complexes.
The conserved pterin dithiolene ligand that coordinates molybdenum (Mo) in the cofactor (Moco) of mononuclear Mo enzymes can exist in both a tricyclic pyranopterin dithiolene form and as a bicyclic pterin-dithiolene form as observed in protein crystal structures of several bacterial molybdoenzymes. Interconversion between the tricyclic and bicyclic forms via pyran scission and cyclization has b...
متن کاملThe tandem ring opening/ring closing metathesis route to oxaspirocycles: an approach to phelligridin G.
Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, we were ultimately able to access this key system through ...
متن کامل6a-Nitro-6-(2,2,7,7-tetramethyltetrahydro-3aH-bis[1,3]dioxolo[4,5-b:4′,5′-d]pyran-5-yl)-6a,6b,7,8,9,11a-hexahydro-6H-spiro[chromeno[3,4-a]pyrrolizine-11,11′-indeno[1,2-b]quinoxaline]
In the title compound, C39H38N4O8, the quinoxaline and indene subunits are essentially planar, with maximum deviations of 0.071 (2) and 0.009 (2) Å, respectively. The indeno-quinoxaline system forms a dihedral angle of 72.81 (3)° with the chromenopyrrolizine system. The two dioxolane rings, as well as the pyran ring of the chromeno group and the terminal pyrrolizine, each adopt an envelope conf...
متن کامل3-{2-[(3-{(E)-2-[4-(Dimethylamino)phenyl]ethenyl}quinoxalin-2-yl)oxy]ethyl}-1,3-oxazolidin-2-one monohydrate
In the title compound, C(23)H(24)N(4)O(3)·H(2)O, the 1,3-oxazoline ring is nearly planar [maximum deviation = 0.059 (2) Å] and its mean plane is twisted by 30.12 (8)° with respect to the quinoxaline fused-ring system; the benzene ring is nearly coplanar with the quinoxaline fused-ring system [dihedral angle = 2.52 (2)°]. The water mol-ecule of crystallization is hydrogen-bond donor to an N atom...
متن کامل(Phenyl)(3-phenylsulfonyl-1,2-dihydropyrrolo[1,2-a]quinoxalin-1-yl)methanone
In the title mol-ecule, C(24)H(18)N(2)O(3)S, the 13-atom ring system comprising the quinoxaline and fused five-membered ring exhibits an r.m.s. deviation from coplanarity of 0.039 Å, with a maximum deviation of 0.0710 (10) Å for the PhCO-bearing C atom of the five-membered ring. The 10-membered C(8)N(2) quinoxaline ring system has an r.m.s. deviation from coplanarity of 0.022 Å, with a maximum ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Dalton transactions
دوره 46 13 شماره
صفحات -
تاریخ انتشار 2017