Exam 23: Lipids

A compound "Z" (C₁₀H₁₆),has $\lambda$ _max at 184 nm in its UV spectrum.Catalytic hydrogenation of Z affords a mixture of diasteromers,which upon separation are identified to be cis-1-isopropyl-4-methylcyclohexane and trans-1-isopropyl-4-methylcyclohexane.Upon ozonolysis,Z yields formaldehyde and 3-acetyl-6-oxoheptanal.Suggest a structure for Z that is consistent with all of the above data,clearly explaining your rationale.

In $\beta$ -carotene,how many tail-to-tail links of isoprene units are there?

Which of the following is a female sex hormone?

Which of these is most likely to have properties resembling natural waxes?

The ozonolysis of a fatty acid produces these fragments: What is the identity of the fatty acid?

Explain how soap removes dirt from clothes.

Complete and name the process:

How many isoprene units are in vitamin A?

Identify the bonds that link the isoprene units in $\alpha$ -farnesene,shown below.How are these units linked: head to head,tail to head or tail to tail ?

Myelin,the protective coating around nerve fibers,is made up of ___________.

Unsaturated fatty acids have a bend in the carbon chain that interferes with packing.Therefore the corresponding triacylglycerols are generally __________ at room temperature and are called _______.

The biosynthesis of one series of prostaglandins begins with which of these fatty acids?

Which is an untrue statement concerning cholesterol?

Which fatty acid is not likely to occur commonly in natural sources?

Which of these reagents would not react with oleic acid?

Of the saturated fatty acids found in fats and oils,this one normally is the most abundant:

In naturally occurring polyunsaturated fatty acids,the stereochemistry of the double bonds is rarely ___________.

How could you synthesize stearolic acid,CH₃(CH₂)₇C $\equiv$ C(CH₂)₇COOH from oleic acid,CH₃(CH₂)₇CH=CH(CH₂)₇COOH?

Salts of long-chain fatty acids are known as ___________.

Fats can be either optically active or inactive,depending on their structure.Draw the structure of an optically active fat that yields 2 equiv of stearic acid and 1 equiv of oleic acid on hydrolysis.Draw the structure of an optically inactive fat that yields the same products.