For each of the following molecules (A-D) determine whether they are chiral, achiral or meso. Choose the most specific answer in each case.

Mannose is a naturally occurring sugar that is important to human metabolism. Mannose can exist in an open chain form (D‑mannose) or can cyclize to form a cyclic structure (α-D‑mannopyranose). Answer the questions below about D‑mannose and α-D‑mannopyranose. Which of the Fischer projections (A-F) below represent D‑mannose? [Fischer]  Which of the chair conformations (T-Z) below represent the MOST stable conformation of α-D‑mannopyranose? [chair1] Which of the chair conformations (T-Z) below represent the LEAST stable conformation of α-D‑mannopyranose? [chair2] How many total possible stereoisomers are there for α-D‑mannopyranose (including the one drawn)? [stereopyr] How many diastereomers are possible for D-mannose? [diasman] The anomeric center of a cyclic sugar is the newly formed chiral center resulting from the cyclization reaction. Which of the carbon atoms labeled 1-6 above is the anomeric center? [anomeric] Identify ONE chair conformation (T-Z) that represents the enantiomer of α-D‑mannopyranose. [enantiomer] What is the relationship between the Fischer projections labeled C and F? [relationship]

Transformational leadership is based on a leader’s________; transactional leadership is based on a leader’s ________.

Rank the following substituents in terms of their Cahn-Ingold-Prelog (CIP) priority (lowest to highest). lowest priority [1] < [2] < [3] < [4] highest priority

Mannose is a naturally occurring sugar that is important to human metabolism. Mannose can exist in an open chain form (D‑mannose) or can cyclize to form a cyclic structure (α-D‑mannopyranose). Answer the questions below about D‑mannose and α-D‑mannopyranose. Which of the Fischer projections (A-F) below represent D‑mannose? [Fischer]  Which of the chair conformations (T-Z) below represent the MOST stable conformation of α-D‑mannopyranose? [chair1] Which of the chair conformations (T-Z) below represent the LEAST stable conformation of α-D‑mannopyranose? [chair2] How many total possible stereoisomers are there for α-D‑mannopyranose (including the one drawn)? [stereopyr] How many diastereomers are possible for D-mannose? [diasman] The anomeric center of a cyclic sugar is the newly formed chiral center resulting from the cyclization reaction. Which of the carbon atoms labeled 1-6 above is the anomeric center? [anomeric] Identify ONE chair conformation (T-Z) that represents the enantiomer of α-D‑mannopyranose. [enantiomer] What is the relationship between the Fischer projections labeled B and D? [relationship]

Mannose is a naturally occurring sugar that is important to human metabolism. Mannose can exist in an open chain form (D‑mannose) or can cyclize to form a cyclic structure (β-D‑mannopyranose). Answer the questions below about D‑mannose and β-D‑mannopyranose. Which of the Fischer projections (A-F) below represent D‑mannose? [Fischer] Which of the chair conformations (T-Z) below represent the MOST stable conformation of β-D‑mannopyranose? [chair1] Which of the chair conformations (T-Z) below represent the LEAST stable conformation of β-D‑mannopyranose? [chair2] How many total possible stereoisomers are there for β-D‑mannopyranose (including the one drawn)? [stereopyr] How many diastereomers are possible for D-mannose? [diasman] The anomeric center of a cyclic sugar is the newly formed chiral center resulting from the cyclization reaction. Which of the carbon atoms labeled 1-6 above is the anomeric center? [anomeric] Identify ONE chair conformation (T-Z) that represents the enantiomer of β-D‑mannopyranose. [enantiomer] What is the relationship between the Fischer projections labeled A and F? [relationship]

Diagnosis and Treatment Upon receiving the information from Luke’s spinal tap, the presence of ameba-like organisms in his CSF was confirmed. He was immediately started on IV therapy with antiprotozoal, antifungal, and antibiotic solutions, including amphotericin B, fluconazole, rifampin, and azithromycin. Dexamethazone was also used in an attempt to counteract the ongoing brain inflammation. Sadly, despite treatment, Luke died within 10 days of returning from his trip.  Question: Luke was most likely infected with which of the following organisms? 

Five (5) of the six (6) molecules shown below have something on common with respect to their stereochemistry. Select the one that is different.

Determine the absolute configuration (R/S) of the chiral centers or E/Z configuration of the alkenes indicated below (A-D). A: [configA] B: [configB] C: [configC] D: [configD]

Five (5) of the six (6) molecules shown below have something on common with respect to their stereochemistry. Select the one that is different.