91431-42-4 Usage
Originator
Lonapalene,Syntex
Manufacturing Process
A solution of sodium nitrate (0.69 g, 10 mmol) in water (5 ml) was added at
0-5°C to a solution of 6-amino-2,3-dimethoxy-1,4-naphthoquinone (1.17 g, 5
mmol) in 5:1 acetic acid:water (25 ml) containing concentrated hydrochloric
acid (1.7 ml). A further quantity of sodium nitrite (0.69 g) was then added to
the reaction mixture after cooling to -5°C, followed by a solution of cuprous
chloride (0.6 g) in concentrated hydrochloric acid (5 ml). The mixture was
allowed to warm to room temperature and solid cuprous chloride was added
portionwise until the mixture assumed a green color. Water was then added to
the reaction mixture and the precipitated yellow solid filtered off, washed with
water and recrystallized from methanol:water (2:1) giving 1.01 g of 6-chloro-
2,3-dimethoxy-1,4-naphthoquinone, melting point 93-94°C (from etherpetrolium ether).
Check Digit Verification of cas no
The CAS Registry Mumber 91431-42-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,1,4,3 and 1 respectively; the second part has 2 digits, 4 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 91431-42:
(7*9)+(6*1)+(5*4)+(4*3)+(3*1)+(2*4)+(1*2)=114
114 % 10 = 4
So 91431-42-4 is a valid CAS Registry Number.
InChI:InChI=1/C16H15ClO6/c1-8(18)22-13-11-6-5-10(17)7-12(11)14(23-9(2)19)16(21-4)15(13)20-3/h5-7H,1-4H3
91431-42-4Relevant articles and documents
A novel Diels-Alder reaction utilizing 3-chloro-1-methoxybutadiene: A short and convergent synthesis of the 5-lipoxygenase inhibitor RS-43179
Flynn,Nies
, p. 5075 - 5078 (1986)
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General Regiospecific Synthesis of Annulated Quinones
Moore, Harold W.,Perri, Steven T.
, p. 996 - 1003 (2007/10/02)
A general regiospecific synthesis of annulated hydroquinones/quinones is presented.This specifically involves the thermal rearrangement of the 4-aryl-4-hydroxycyclobutenones 1a-k to the corresponding annulated hydroquinones.The synthetic scope and mechani
SYNTHESIS OF LONAPALENE.
Perri, Steven T.,Moore, Harold W.
, p. 4507 - 4510 (2007/10/02)
An efficient and practical synthesis of the antipsoriatic drug Lonapalene is reported.This involves the thermal rearrangement of 4-(4-chlorophenyl)-4-hydroxy-2,3-dimethoxycyclobutenone to 6-chloro-1,4-dihydroxynaphthalene wich was converted to Lonapalene upon treatment with acetic anhydride/pyridine.
