Five flavonoidal compounds were successively isolated and identified from the ethanolic extract of the fruits of Faidherbia albida. Two of them were previously isolated from the leaves of Faidherbia albida, such as Rhamnocitrin (F-1) and Quercetin (F-4), the other three are firstly reported for isolation from the fruit, and named Dihydrokaempferol (F-2), Luteolin (F-3) and Rutin (F-5). The structures were identified and confirmed through different spectroscopic methods including 1H-NMR, 13C-NMR and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPPH method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially the total ethanolic extract, chloroform and ethyl acetate fractions of the fruits.

Eight phenolic compounds were successively isolated and identified from the ethanolic extract of the leaves of Faidherbia albida. Five of them were previously isolated from the genus Acacia, such as β- amyrin (L-1), β-sitosterol (L-2), β-sitosterol-3-O-β-D-glucopyranoside.(L-3), Quercetin (L-5) and Gallic acid (L-6), the other three are firstly reported for isolation from the genus Acacia, and named Rhamnocitrin (L-4), Afzelin (L-7) and (6S, 9S)- Roseoside (L-8). The structures were identified and confirmed through different spectroscopic methods including 1H-NMR, 13C-NMR, HMBC and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPPH method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially ethyl acetate and aqueous fractions of the leaves.

Eight phenolic compounds were successively isolated and identified from the ethanolic extract of the leaves of Faidherbia albida. Five of them were previously isolated from the genus Acacia, such as β- amyrin (L-1), β-sitosterol (L-2), β-sitosterol-3-O-β-D-glucopyranoside.(L-3), Quercetin (L-5) and Gallic acid (L-6), the other three are firstly reported for isolation from the genus Acacia, and named Rhamnocitrin (L-4), Afzelin (L-7) and (6S, 9S)- Roseoside (L-8). The structures were identified and confirmed through different spectroscopic methods including 1H-NMR, 13C-NMR, HMBC and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPPH method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially ethyl acetate and aqueous fractions of the leaves.

Eight phenolic compounds were successively isolated and identified from the ethanolic extract of the leaves of Faidherbia albida. Five of them were previously isolated from the genus Acacia, such as β- amyrin (L-1), β-sitosterol (L-2), β-sitosterol-3-O-β-D-glucopyranoside.(L-3), Quercetin (L-5) and Gallic acid (L-6), the other three are firstly reported for isolation from the genus Acacia, and named Rhamnocitrin (L-4), Afzelin (L-7) and (6S, 9S)- Roseoside (L-8). The structures were identified and confirmed through different spectroscopic methods including 1H-NMR, 13C-NMR, HMBC and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPPH method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially ethyl acetate and aqueous fractions of the leaves.

Eight phenolic compounds were successively isolated and identified from the ethanolic extract of the leaves of Faidherbia albida. Five of them were previously isolated from the genus Acacia, such as β- amyrin (L-1), β-sitosterol (L-2), β-sitosterol-3-O-β-D-glucopyranoside.(L-3), Quercetin (L-5) and Gallic acid (L-6), the other three are firstly reported for isolation from the genus Acacia, and named Rhamnocitrin (L-4), Afzelin (L-7) and (6S, 9S)- Roseoside (L-8). The structures were identified and confirmed through different spectroscopic methods including 1H-NMR, 13C-NMR, HMBC and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPPH method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially ethyl acetate and aqueous fractions of the leaves.

Background: Hypertension represents a widespread cardiovascular condition although usually asymptomatic, is a major risk factor for myocardial ischemia, renal failure and stroke. Amlodipine is considered a powerful dihydropyridine calcium channel blocker used as antihypertensive agent. Its mechanism of action depend on relaxing the smooth muscle of the artery wall and decrease peripheral resistance. Methods: An accurate, sensitive and robust chiral HPLC method was developed for separation and quantitation of S(-)- amlodipine simultaneously in the presence of its R(+)- isomer. Chiral separation was applied using Daicel CROWNPAK CR(+) (5 µm, 4.0x150 mm) column which contains (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6-ether coated into a 5 µm reversed phase silica support. The mobile phase system was aqueous acidic 70% HClO4 (pH 2.0) and methanol in the proportion of (95:5 v/v), filtered through 0.45 µm membrane and degassed by before use, pumped at a flow rate was 0.8 mL min-1 with UV detector adjusted at 238 nm. Results: The chromatographic HPLC method was validated with respect to ICH guidelines. Linear concentration range was 5-60 µg mL-1 with correlation coefficient (r) about 0.9998, the detection and quantitation limits was found 1.66 and 5.05 µg m-1; respectively. Accuracy was evaluated using standard addition technique with mean recovery about 98.40% while precision was assessed at intraday and interday level. It was found that all %RSD values below 2% Conclusion: A simple, enantioselective, chiral HPLC method was developed and validated for the quantitation of amlodipine [S-(+)- isomer] in racemic tablets using CROWNPAK CR(+) chiral stationary phase. The proposed method is specific, precise, accurate, and robust which can be successfully applied for the routine analysis of S-AML in bulk and pharmaceutical dosage formulations.

Direct-acting antivirals (DAAs) represent a revolution in the treatment of chronic hepatitis C which have emerged at an extremely rapid pace over the past few years. DAAs act directly on the hepatitis C virus at various points in the viral life cycle to inhibit viral production. Among these novel DAAs, are daclatasvir (DCS) and ledipasvir (LDS). Herein, a novel, fast, simple, ultrasensitive and cost-effective spectrofluorimetric method was designed for determination of DCS and LDS in miscellaneous matrices. The method is based on investigation of the native fluorescence of the cited drugs. The relative fluorescence intensity (RFI) was measured at ex/em equal to 315/381 nm for DCS and 332/387 nm for LDS. Under the optimum conditions, the linear ranges of calibration curves were 0.2-30 and 6-120 ng mL-1 for DCS and LDS, respectively with correlation coefficients 0.9998. The detection limits were 0.047 and 1.939 ng mL-1 for DCS and LDS, respectively indicating ultrasensitivity of the proposed method. Consequently, this permits in vitro and in vivo application of the proposed method in spiked and real human plasma with good percentage recovery (96.6–103.6%). The method was validated in compliance with ICH guidelines and US-FDA guidelines. Furthermore, the application was extended to analysis of DCS and LDS in its pharmaceutical formulations (either alone or in presence of other co-formulated drugs) and in synthetic mixture with sofosbuvir or ribavirin.

Direct-acting antivirals (DAAs) represent a revolution in the treatment of chronic hepatitis C which have emerged at an extremely rapid pace over the past few years. DAAs act directly on the hepatitis C virus at various points in the viral life cycle to inhibit viral production. Among these novel DAAs, are daclatasvir (DCS) and ledipasvir (LDS). Herein, a novel, fast, simple, ultrasensitive and cost-effective spectrofluorimetric method was designed for determination of DCS and LDS in miscellaneous matrices. The method is based on investigation of the native fluorescence of the cited drugs. The relative fluorescence intensity (RFI) was measured at ex/em equal to 315/381 nm for DCS and 332/387 nm for LDS. Under the optimum conditions, the linear ranges of calibration curves were 0.2-30 and 6-120 ng mL-1 for DCS and LDS, respectively with correlation coefficients 0.9998. The detection limits were 0.047 and 1.939 ng mL-1 for DCS and LDS, respectively indicating ultrasensitivity of the proposed method. Consequently, this permits in vitro and in vivo application of the proposed method in spiked and real human plasma with good percentage recovery (96.6–103.6%). The method was validated in compliance with ICH guidelines and US-FDA guidelines. Furthermore, the application was extended to analysis of DCS and LDS in its pharmaceutical formulations (either alone or in presence of other co-formulated drugs) and in synthetic mixture with sofosbuvir or ribavirin.

Direct-acting antivirals (DAAs) represent a revolution in the treatment of chronic hepatitis C which have emerged at an extremely rapid pace over the past few years. DAAs act directly on the hepatitis C virus at various points in the viral life cycle to inhibit viral production. Among these novel DAAs, are daclatasvir (DCS) and ledipasvir (LDS). Herein, a novel, fast, simple, ultrasensitive and cost-effective spectrofluorimetric method was designed for determination of DCS and LDS in miscellaneous matrices. The method is based on investigation of the native fluorescence of the cited drugs. The relative fluorescence intensity (RFI) was measured at ex/em equal to 315/381 nm for DCS and 332/387 nm for LDS. Under the optimum conditions, the linear ranges of calibration curves were 0.2-30 and 6-120 ng mL-1 for DCS and LDS, respectively with correlation coefficients 0.9998. The detection limits were 0.047 and 1.939 ng mL-1 for DCS and LDS, respectively indicating ultrasensitivity of the proposed method. Consequently, this permits in vitro and in vivo application of the proposed method in spiked and real human plasma with good percentage recovery (96.6–103.6%). The method was validated in compliance with ICH guidelines and US-FDA guidelines. Furthermore, the application was extended to analysis of DCS and LDS in its pharmaceutical formulations (either alone or in presence of other co-formulated drugs) and in synthetic mixture with sofosbuvir or ribavirin.

Direct-acting antivirals (DAAs) represent a revolution in the treatment of chronic hepatitis C which have emerged at an extremely rapid pace over the past few years. DAAs act directly on the hepatitis C virus at various points in the viral life cycle to inhibit viral production. Among these novel DAAs, are daclatasvir (DCS) and ledipasvir (LDS). Herein, a novel, fast, simple, ultrasensitive and cost-effective spectrofluorimetric method was designed for determination of DCS and LDS in miscellaneous matrices. The method is based on investigation of the native fluorescence of the cited drugs. The relative fluorescence intensity (RFI) was measured at ex/em equal to 315/381 nm for DCS and 332/387 nm for LDS. Under the optimum conditions, the linear ranges of calibration curves were 0.2-30 and 6-120 ng mL-1 for DCS and LDS, respectively with correlation coefficients 0.9998. The detection limits were 0.047 and 1.939 ng mL-1 for DCS and LDS, respectively indicating ultrasensitivity of the proposed method. Consequently, this permits in vitro and in vivo application of the proposed method in spiked and real human plasma with good percentage recovery (96.6–103.6%). The method was validated in compliance with ICH guidelines and US-FDA guidelines. Furthermore, the application was extended to analysis of DCS and LDS in its pharmaceutical formulations (either alone or in presence of other co-formulated drugs) and in synthetic mixture with sofosbuvir or ribavirin.