Treatment of Pulmonary Disease

1 . A method of treating, reducing the risk of, preventing, or alleviating a pulmonary disease or condition in a subject, comprising administering to the subject a therapeutically effective amount of a compound of formula A:

or a pharmaceutically acceptable salt thereof, wherein:

R 1 is hydrogen or unsubstituted C 1 -C 6 alkyl;

R 2 is hydrogen or α-hydroxyl;

X is C(O)OH, C(O)NH(CH 2 ) m SO 3 H, C(O)NH(CH 2 ) n CO 2 H, or OSO 3 H;

R 4 is hydroxyl or hydrogen;

R 7 is hydroxyl or hydrogen;

m is an integer 1, 2, or 3; and

n is an integer 1, 2, or 3.

2 . The method of claim 1 , wherein R 1 is unsubstituted C 1 -C 6 alkyl.

3 . The method of claim 2 , wherein R 1 is methyl, ethyl, or propyl.

4 . The method of claim 3 , wherein R 1 is ethyl.

5 . The method of claim 1 , wherein R 1 is selected from methyl, ethyl and propyl; R 4 is OH; R 7 is H; and R 2 is H.

6 . The method of claim 1 , wherein the compound is selected from

or a pharmaceutically acceptable salt thereof.

7 . The method of claim 1 , wherein the compound is

or a pharmaceutically acceptable salt thereof.

8 . The method of claim 1 , wherein the compound is

or a pharmaceutically acceptable salt thereof.

9 . The method of claim 1 , wherein the compound is a pharmaceutically acceptable salt.

10 . The method of claim 9 , wherein the salt is sodium salt or a triethylammonium salt.

11 . The method of claim 1 , wherein the pulmonary disease or condition is selected from obstructive pulmonary disease (COPD), emphysema, asthma, idiopathic pulmonary fibrosis, pneumonia, tuberculosis, cystic fibrosis, bronchitis, pulmonary hypertension (e.g., Idiopathic Pulmonary Arterial Hypertension (IPAH) (also known as Primary Pulmonary Hypertension (PPH)) and Secondary Pulmonary Hypertension (SPH)), interstitial lung disease, and lung cancer.

12 . The method of claim 11 , wherein the pulmonary disease or condition is selected from COPD, emphysema, asthma, cystic fibrosis, and pulmonary hypertension.

13 . The method of claim 12 , wherein the pulmonary disease or condition is pulmonary hypertension.

14 . The method of claim 13 , wherein the pulmonary hypertension is IPAH or SPH.

15 . The method of claim 1 , wherein the pulmonary disease or condition is caused by inflammation, autoimmune disease, scleroderma, rheumatoid arthritis, Acute Lung Injury (ALI), Acute Respiratory Distress Syndrome (ARDS), birth defect of the heart, blood clot in the lungs (pulmonary embolism), congestive heart failure, heart valve disease, HIV infection, extended periods of low oxygen levels in the blood, medication, substance of abuse, or obstructive sleep apnea.

16 . The method of claim 15 , wherein the pulmonary disease or condition is caused by inflammation.

17 . The method of claim 1 , wherein the subject is a human.

18 . The method of claim 1 , wherein the compound is administered systemically, orally, intravenously, intramuscularly, intraperitoneally, or by inhalation.

19 . A method of reducing or suppressing inflammation in the lung in a subject, comprising administering to the subject in need thereof a therapeutically effective amount of a compound of formula A:

or a pharmaceutically acceptable salt thereof, wherein:

R 1 is hydrogen or unsubstituted C 1 -C 6 alkyl;

R 2 is hydrogen or α-hydroxyl;

X is C(O)OH, C(O)NH(CH 2 ) m SO 3 H, C(O)NH(CH 2 ) n CO 2 H, or OSO 3 H;

R 4 is hydroxyl or hydrogen;

R 7 is hydroxyl or hydrogen;

m is 1, 2, or 3; and

n is 1, 2, or 3.

20 . A method of promoting lung repair in a subject, comprising administering to the subject in need thereof a therapeutically effective amount of a compound of formula A:

or a pharmaceutically acceptable salt thereof, wherein:

R 1 is hydrogen or unsubstituted C 1 -C 6 alkyl;

R 2 is hydrogen or a-hydroxyl;

X is C(O)OH, C(O)NH(CH 2 ) m SO 3 H, C(O)NH(CH 2 ) n CO 2 H, or OSO 3 H;

R 4 is hydroxyl or hydrogen;

R 7 is hydroxyl or hydrogen;

m is 1, 2, or 3; and

n is 1, 2, or 3.