Publications by authors named "Dolas A"

Construction of a chiral methanamine unit at the C3 position of pyrrole is highly desirable; nevertheless, it remains challenging due to its intrinsic electronic properties. Herein, we present an operationally straightforward and direct asymmetric approach for accessing α-(3-pyrrolyl)methanamines under benign organocatalytic conditions for the first time. The one-pot transformation proceeds smoothly through an amine-catalyzed direct Mannich reaction of succinaldehyde with various -cyclic imines, followed by a Paal-Knorr cyclization with a primary amine.

View Article and Find Full Text PDF

Due to its structural complexity and intrinsic sensitivity of bridged aminal junction, 2,6-diazabicyclo[2.2.2]octane (2,6-DABCO) has remained a highly desirable target in synthetic chemistry.

View Article and Find Full Text PDF
Article Synopsis
  • A middle-aged woman experienced difficulty breathing and a chronic cough three months after undergoing mitral valve replacement surgery, prompting further evaluation of her respiratory symptoms.
  • Imaging revealed an elevated right hemidiaphragm and a strange opacity in the right lower lobe, leading to a diagnosis of right hemidiaphragm palsy from a possible phrenic nerve injury during her prior surgery.
  • Despite the recommendation for a diaphragmatic plication due to significant breathing issues and potential complications, the patient was hesitant about undergoing another surgery and needed time to consider her options.
View Article and Find Full Text PDF

A straightforward method has been developed to synthesize 2-aryl-3-(2-aminoaryl) quinoxalines from 2-arylindoles and 1,2-diaminoarenes under mild electrochemical conditions. The reaction proceeds through in situ generations of 2-arylindole-3-ones under electrochemical oxidative dearomatization of 2-arylindoles, followed by a ring opening-cyclization sequence with 1,2-diaminoarenes. A series of 2-aryl-3-(2-aminoaryl) quinoxalines have been prepared with moderate to good yields (up to 75%).

View Article and Find Full Text PDF

Creating functionality with chirality at position C3 of pyrrole is challenging. An operationally simple organocatalytic method has been developed to generate functionality with a chiral tertiary/quaternary stereocenter at position C3 of pyrrole. The process proceeds through an amine-catalyzed direct aldol reaction of succinaldehyde with various acceptor carbonyls, followed by a Paal-Knorr reaction with a primary amine in the same pot.

View Article and Find Full Text PDF

An operationally simple catalyst-free protocol for the direct regiospecific synthesis of β-(C3)-substituted pyrroles has been developed. The enamine intermediate, generated from succinaldehyde and a primary amine, was trapped with activated carbonyls before the Paal-Knorr reaction in a direct multicomponent "just-mix" fashion to furnish pyrroles with overall good yields. Several C3-substituted -alkyl/aryl/H pyrroles have been produced under open-flask conditions with high atom economy and avoiding protection-deprotection chemistry.

View Article and Find Full Text PDF

Pulmonary hamartomas are rare tumors and are mostly found incidentally in patients investigated for other pathologies. They are frequently small in size, though with some being reported as large as 25 centimeters (cm). We are reporting a case of a huge pulmonary hamartoma (measuring 25.

View Article and Find Full Text PDF

A direct aza-Diels-Alder reaction between 2-aryl-3-indolin-3-ones and cyclic-enones has been developed to access chiral indolin-3-one fused polycyclic bridged compounds. This method proceeds via proline-catalyzed Barbas-dienamine intermediate formation from various cyclic-enones such as 2-cyclopenten-1-one, 2-cyclohexene-1-one, and 2-cycloheptene-1-one, followed by a reaction with 2-aryl-3-indol-3-ones. Several indolin-3-ones fusing [2.

View Article and Find Full Text PDF

Cathepsin D, an aspartyl protease, is an attractive therapeutic target for various diseases, primarily cancer and osteoarthritis. However, despite several small molecule cathepsin D inhibitors being developed, that are highly potent, most of them show poor microsomal stability, which in turn limits their clinical translation. Herein, we describe the design, optimization and evaluation of a series of novel non-peptidic acylguanidine based small molecule inhibitors of cathepsin D.

View Article and Find Full Text PDF

Dietary and lifestyle changes are leading to an increased occurrence of non-alcoholic fatty liver disease (NAFLD). Using a hyperlipidemic murine model for non-alcoholic steatohepatitis (NASH), we have previously demonstrated that the lysosomal protease cathepsin D (CTSD) is involved with lipid dysregulation and inflammation. However, despite identifying CTSD as a major player in NAFLD pathogenesis, the specific role of extracellular CTSD in NAFLD has not yet been investigated.

View Article and Find Full Text PDF

Niemann-Pick Type C1 disorder (NPC) is a rare lysosomal storage disease characterized by the accumulation of cholesterol in lysosomes. NPC has no FDA approved treatments yet, however 2-hydroxypropyl-β-cyclodextrin (HPβCD) has shown efficacy for treating the disease in both mouse and feline NPC models and is currently being investigated in late stage clinical trials. Despite promising results, therapeutic use of HPβCD is limited by the need for high doses, ototoxicity and intrathecal administration.

View Article and Find Full Text PDF

Thyroid dysfunction causes remarkable cardiovascular derangements. Both systolic and diastolic dysfunction of the heart can occur in hypothyroidism leading to cardiac arrhythmia and congestive heart failure. Refractory cardiogenic shock and hypotension in congenital hypothyroidism is rare.

View Article and Find Full Text PDF