Fast colorimetric titration protocol for quantification of boron tribromide

Acids IIa-c were prepared by reactions of (4-fluoro-2-iodophenyl)acetic acid with 4-methoxythiophenol, 4-ethoxythiophenol and 4-(ethylthio)thiophenol and cyclized with polyphosphoric acid in boiling toluene to dibenzo[b,f]thiepin-10(11H)-ones IIIa-c. Reduction with sodium borohydride afforded the alcohols IVa-c which were treated with hydrogen chloride and gave the chloro derivatives Va-c. Substitution reactions with 1-methylpiperazine resulted in the title compounds Ia-c out of which the methoxy derivative Ia was transformed by demethylation with boron tribromide to the phenol Id. Compounds Ia-d are very potent neuroleptics exhibiting a clear prolongation of the central depressant and some prolongation of the cataleptic activity.

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Reactivity of Sodium Hexaethyl-2,4-dicarba-nido-hexaborate(1-)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990977 ◽

1999 ◽

Vol 64 (6) ◽

pp. 977-985 ◽

Cited By ~ 17

Author(s):

Bernd Wrackmeyer ◽

Hans-Jörg Schanz ◽

Wolfgang Milius ◽

Catherine McCammon

Keyword(s):

Mössbauer Spectroscopy ◽

Nmr Spectroscopy ◽

Structural Analysis ◽

Hydrogen Atom ◽

Mossbauer Spectroscopy ◽

Sandwich Complex ◽

X Ray ◽

Bromo Derivative ◽

Boron Tribromide ◽

C Nmr

Sodium hexaethyl-2,4-dicarba-nido-hexaborate(1-) (6), available from hexaethyl-2,4-dicarba- nido-hexaborane(8) (4) by deprotonation, reacts with deuterated methanol, CD3OD, to give back 4 without H/D exchange of the B-H-B hydrogen atom. The reaction of 6 with diethylboron chloride, Et2BCl, affords hexaethyl-2,4-dicarba-closo-hexaborane(6) (7), the first example of a peralkylated carborane of this type. In contrast, the reaction of 6 with boron tribromide, BBr3, leads mainly to 2,3,4,5,6,7-hexaethyl-2,4-dicarba-closo-heptaborane(7) (8), together with the corresponding 1-bromo derivative (9) and the closo-carborane 7 as side products. The reaction of two equivalents of 6 with FeCl2 gives the air-stable sandwich complex bis[hexaethyl-2,4-dicarba-nido-hexaborate(1-)]iron 10 which was characterised by X-ray structural analysis. All products were characterised by 1H, 11B and 13C NMR spectroscopy, and 57Fe Mössbauer spectroscopy was used to study 10.

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A new rapid titration protocol for lamotrigine that reduces the risk of skin rash

Epilepsia Open ◽

10.1002/epi4.12495 ◽

2021 ◽

Author(s):

Yoonhyuk Jang ◽

Jangsup Moon ◽

Narae Kim ◽

Tae‐Joon Kim ◽

Jin‐Sun Jun ◽

...

Keyword(s):

Skin Rash ◽

Titration Protocol

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Formulation and Stability of Naltrexone Oral Liquid for Rapid Withdrawal from Methadone

Annals of Pharmacotherapy ◽

10.1177/106002809703101102 ◽

1997 ◽

Vol 31 (11) ◽

pp. 1291-1295 ◽

Cited By ~ 4

Author(s):

J Paul Fawcett ◽

Nicola C Morgan ◽

David J Woods

Keyword(s):

Methadone Maintenance Treatment ◽

Methadone Maintenance ◽

Withdrawal Symptoms ◽

Dose Titration ◽

Oral Liquid ◽

Naltrexone Treatment ◽

Flexible Dosing ◽

Drug Dependent ◽

The Stability ◽

Titration Protocol

OBJECTIVE: To assess the stability of naltrexone oral liquid prepared from tablets and powder, and to evaluate its use in precipitating rapid withdrawal from methadone. DESIGN: Naltrexone 1 mg/mL oral liquids were prepared from tablets and powder and stored in the dark at 4, 25, and 70 °C. Similar formulations containing 5 mg/mL were stored at 70 °C. The 1-mg/mL formulation prepared from tablets was clinically evaluated in inducing rapid withdrawal in two drug-dependent individuals receiving methadone maintenance treatment using a naltrexone dose titration protocol. SETTING: A university pharmacy school and affiliated urban teaching hospital. MAIN OUTCOME MEASURES: Samples removed at six time points were analyzed for naltrexone concentration to assess decomposition over 90 days. An opioid withdrawal symptom checklist was used to assess the severity of the withdrawal symptoms prior to, and 30 minutes after, each dose of naltrexone. RESULTS: Decomposition of naltrexone in all formulations stored at 4 and 25 °C was not significant over 90 days. Both patients tolerated naltrexone 1 mg/mL oral liquid, but found it bitter and gritty. Withdrawal symptoms were experienced immediately after the first dose, but were resolving by the end of day 3 of naltrexone treatment, at which stage both patients were able to tolerate a 50-mg tablet of naltrexone as maintenance. CONCLUSIONS: Naltrexone 1 mg/mL oral liquids prepared from tablets or powder are stable when stored in the dark for 60 days at 4 °C and for 30 days at 25 °C. The formulation prepared from tablets provides flexible dosing in patients undergoing rapid withdrawal from methadone.

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Preparation of Some 2-(Methoxyphenyl)-2H-benzotriazoles and the Corresponding Hydroxyphenyl Compounds

Australian Journal of Chemistry ◽

10.1071/ch9871663 ◽

1987 ◽

Vol 40 (10) ◽

pp. 1663 ◽

Cited By ~ 3

Author(s):

J Rosevear ◽

JFK Wilshire

Keyword(s):

Acetic Acid ◽

Good Yield ◽

Hydrobromic Acid ◽

Methoxy Group ◽

Methylene Chloride ◽

Thiourea Dioxide ◽

Boron Tribromide

The reaction of several substituted o- nitronitrosobenzenes with O- and p- anisidine , and 2,4- dimethoxyaniline in acetic acid gives in good yield the corresponding enitroazobenzenes which are readily reduced with thiourea dioxide ( formamidinesulfinic acid) to the corresponding 2-(methoxypheny1)-2H-benzotriazoles, demethylation of which furnished the corresponding 2- (hydroxypheny1)-2H-benzotriazoles. Demethylation of the dimethoxy derivatives was best accomplished with boron tribromide in methylene chloride, the methoxy group located ortho to the benzotriazole ring being demethylated more readily than is the para-methoxy group. The reaction of enitroazobenzenes containing a methoxy group with hydrobromic acid in acetic acid results in cleavage of the azo bond and also partial bromination to give o- nitroaniline and some of its brominated derivatives.

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